diff --git a/src/dopt_pollublock_blockchain/blockchain.cpp b/src/dopt_pollublock_blockchain/blockchain.cpp
index 620a291..567b2c3 100644
--- a/src/dopt_pollublock_blockchain/blockchain.cpp
+++ b/src/dopt_pollublock_blockchain/blockchain.cpp
@@ -1586,7 +1586,7 @@ static const char* const __pyx_f[] = {
 
 /* #### Code section: numeric_typedefs ### */
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":26
+/* "dopt_pollublock_blockchain/blockchain.pyx":27
  * 
  * 
  * ctypedef unsigned long ULong             # <<<<<<<<<<<<<<
@@ -1603,7 +1603,7 @@ struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_Blockchain;
 struct __pyx_opt_args_26dopt_pollublock_blockchain_10blockchain_7PyBlock_from_ptr;
 struct __pyx_opt_args_26dopt_pollublock_blockchain_10blockchain_mine_block;
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":27
+/* "dopt_pollublock_blockchain/blockchain.pyx":28
  * 
  * ctypedef unsigned long ULong
  * ctypedef unordered_map[uint64_t, Block*] BcHashmap             # <<<<<<<<<<<<<<
@@ -1612,7 +1612,7 @@ struct __pyx_opt_args_26dopt_pollublock_blockchain_10blockchain_mine_block;
 */
 typedef std::unordered_map<uint64_t,::Block *>  __pyx_t_26dopt_pollublock_blockchain_10blockchain_BcHashmap;
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":122
+/* "dopt_pollublock_blockchain/blockchain.pyx":123
  * 
  *     @staticmethod
  *     cdef PyBlock from_ptr(Block *block, bint owner=False):             # <<<<<<<<<<<<<<
@@ -1624,7 +1624,7 @@ struct __pyx_opt_args_26dopt_pollublock_blockchain_10blockchain_7PyBlock_from_pt
   int owner;
 };
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":291
+/* "dopt_pollublock_blockchain/blockchain.pyx":302
  * 
  * 
  * cdef int mine_block(Block *block, unsigned int difficulty, uint64_t *nonce_solution, unsigned int max_nonce=0xFFFFFFFF) nogil:             # <<<<<<<<<<<<<<
@@ -1636,7 +1636,7 @@ struct __pyx_opt_args_26dopt_pollublock_blockchain_10blockchain_mine_block {
   unsigned int max_nonce;
 };
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":86
+/* "dopt_pollublock_blockchain/blockchain.pyx":87
  * 
  * 
  * cdef class PyBlock:             # <<<<<<<<<<<<<<
@@ -1651,7 +1651,7 @@ struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock {
 };
 
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":322
+/* "dopt_pollublock_blockchain/blockchain.pyx":333
  * 
  * 
  * cdef class Blockchain:             # <<<<<<<<<<<<<<
@@ -1673,7 +1673,7 @@ struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_Blockchain {
 
 
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":86
+/* "dopt_pollublock_blockchain/blockchain.pyx":87
  * 
  * 
  * cdef class PyBlock:             # <<<<<<<<<<<<<<
@@ -1687,7 +1687,7 @@ struct __pyx_vtabstruct_26dopt_pollublock_blockchain_10blockchain_PyBlock {
 static struct __pyx_vtabstruct_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_vtabptr_26dopt_pollublock_blockchain_10blockchain_PyBlock;
 
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":322
+/* "dopt_pollublock_blockchain/blockchain.pyx":333
  * 
  * 
  * cdef class Blockchain:             # <<<<<<<<<<<<<<
@@ -2804,17 +2804,18 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_2__init__
 static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_4__dealloc__(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_6__repr__(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_8__str__(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
-static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_10serialize_dict(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_10as_dataclass(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_12serialize_dict(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_5index___get__(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_9timestamp___get__(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_4data___get__(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_9prev_hash___get__(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_5nonce___get__(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_4hash___get__(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
-static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_12bytes_serialize(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
-static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_14perform_hash(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
-static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_16__reduce_cython__(CYTHON_UNUSED struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
-static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_18__setstate_cython__(CYTHON_UNUSED struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self, CYTHON_UNUSED PyObject *__pyx_v___pyx_state); /* proto */
+static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_14bytes_serialize(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_16perform_hash(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_18__reduce_cython__(CYTHON_UNUSED struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_20__setstate_cython__(CYTHON_UNUSED struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *__pyx_v_self, CYTHON_UNUSED PyObject *__pyx_v___pyx_state); /* proto */
 static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain___cinit__(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_Blockchain *__pyx_v_self, CYTHON_UNUSED PyObject *__pyx_v_args, CYTHON_UNUSED PyObject *__pyx_v_kwargs); /* proto */
 static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_2__init__(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_Blockchain *__pyx_v_self, PyObject *__pyx_v_db_path); /* proto */
 static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_4__dealloc__(struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_Blockchain *__pyx_v_self); /* proto */
@@ -2867,8 +2868,8 @@ typedef struct {
   __Pyx_CachedCFunction __pyx_umethod_PyDict_Type_pop;
   __Pyx_CachedCFunction __pyx_umethod_PyDict_Type_values;
   PyObject *__pyx_tuple[1];
-  PyObject *__pyx_codeobj_tab[17];
-  PyObject *__pyx_string_tab[189];
+  PyObject *__pyx_codeobj_tab[18];
+  PyObject *__pyx_string_tab[200];
   PyObject *__pyx_number_tab[1];
 /* #### Code section: module_state_contents ### */
 /* CommonTypesMetaclass.module_state_decls */
@@ -2925,27 +2926,27 @@ static __pyx_mstatetype * const __pyx_mstate_global = &__pyx_mstate_global_stati
 #define __pyx_kp_u_Hash __pyx_string_tab[12]
 #define __pyx_kp_u_Hash_mismatch_Hash_of_previous __pyx_string_tab[13]
 #define __pyx_kp_u_Hashes_to_not_match_Abort __pyx_string_tab[14]
-#define __pyx_kp_u_Index __pyx_string_tab[15]
+#define __pyx_kp_u_Index_2 __pyx_string_tab[15]
 #define __pyx_kp_u_Index_value_is_out_of_bounds __pyx_string_tab[16]
 #define __pyx_kp_u_Maximum_number_must_be_greater_t __pyx_string_tab[17]
-#define __pyx_kp_u_Prev_Hash __pyx_string_tab[18]
-#define __pyx_kp_u_Provided_index_not_found __pyx_string_tab[19]
-#define __pyx_kp_u_PyBlock_Index __pyx_string_tab[20]
-#define __pyx_kp_u_The_parent_directory_of_the_prov __pyx_string_tab[21]
-#define __pyx_kp_u_UTF_8 __pyx_string_tab[22]
-#define __pyx_kp_u__2 __pyx_string_tab[23]
-#define __pyx_kp_u__3 __pyx_string_tab[24]
-#define __pyx_kp_u__4 __pyx_string_tab[25]
-#define __pyx_kp_u_disable __pyx_string_tab[26]
-#define __pyx_kp_u_enable __pyx_string_tab[27]
-#define __pyx_kp_u_gc __pyx_string_tab[28]
-#define __pyx_kp_u_isenabled __pyx_string_tab[29]
-#define __pyx_kp_u_no_default___reduce___due_to_non __pyx_string_tab[30]
-#define __pyx_kp_u_nonce_2 __pyx_string_tab[31]
-#define __pyx_kp_u_sqlite __pyx_string_tab[32]
-#define __pyx_kp_u_src_dopt_pollublock_blockchain_b __pyx_string_tab[33]
-#define __pyx_kp_u_stringsource __pyx_string_tab[34]
-#define __pyx_kp_u_timestamp_2 __pyx_string_tab[35]
+#define __pyx_kp_u_Nonce __pyx_string_tab[18]
+#define __pyx_kp_u_Prev_Hash __pyx_string_tab[19]
+#define __pyx_kp_u_Provided_index_not_found __pyx_string_tab[20]
+#define __pyx_kp_u_PyBlock_Index __pyx_string_tab[21]
+#define __pyx_kp_u_The_parent_directory_of_the_prov __pyx_string_tab[22]
+#define __pyx_kp_u_Timestamp __pyx_string_tab[23]
+#define __pyx_kp_u_UTF_8 __pyx_string_tab[24]
+#define __pyx_kp_u__2 __pyx_string_tab[25]
+#define __pyx_kp_u__3 __pyx_string_tab[26]
+#define __pyx_kp_u__4 __pyx_string_tab[27]
+#define __pyx_kp_u_disable __pyx_string_tab[28]
+#define __pyx_kp_u_enable __pyx_string_tab[29]
+#define __pyx_kp_u_gc __pyx_string_tab[30]
+#define __pyx_kp_u_isenabled __pyx_string_tab[31]
+#define __pyx_kp_u_no_default___reduce___due_to_non __pyx_string_tab[32]
+#define __pyx_kp_u_sqlite __pyx_string_tab[33]
+#define __pyx_kp_u_src_dopt_pollublock_blockchain_b __pyx_string_tab[34]
+#define __pyx_kp_u_stringsource __pyx_string_tab[35]
 #define __pyx_n_u_Blockchain __pyx_string_tab[36]
 #define __pyx_n_u_Blockchain___reduce_cython __pyx_string_tab[37]
 #define __pyx_n_u_Blockchain___setstate_cython __pyx_string_tab[38]
@@ -2959,146 +2960,157 @@ static __pyx_mstatetype * const __pyx_mstate_global = &__pyx_mstate_global_stati
 #define __pyx_n_u_Blockchain_print_blocks __pyx_string_tab[46]
 #define __pyx_n_u_Blockchain_save __pyx_string_tab[47]
 #define __pyx_n_u_Blockchain_validate __pyx_string_tab[48]
-#define __pyx_n_u_Path __pyx_string_tab[49]
-#define __pyx_n_u_PyBlock __pyx_string_tab[50]
-#define __pyx_n_u_PyBlock___reduce_cython __pyx_string_tab[51]
-#define __pyx_n_u_PyBlock___setstate_cython __pyx_string_tab[52]
-#define __pyx_n_u_PyBlock_bytes_serialize __pyx_string_tab[53]
-#define __pyx_n_u_PyBlock_perform_hash __pyx_string_tab[54]
-#define __pyx_n_u_PyBlock_serialize_dict __pyx_string_tab[55]
-#define __pyx_n_u_Pyx_PyDict_NextRef __pyx_string_tab[56]
-#define __pyx_n_u_TIMEZONE_UTC __pyx_string_tab[57]
-#define __pyx_n_u_asc __pyx_string_tab[58]
-#define __pyx_n_u_asyncio_coroutines __pyx_string_tab[59]
-#define __pyx_n_u_batch __pyx_string_tab[60]
-#define __pyx_n_u_batch_size __pyx_string_tab[61]
-#define __pyx_n_u_begin __pyx_string_tab[62]
-#define __pyx_n_u_block __pyx_string_tab[63]
-#define __pyx_n_u_blocks __pyx_string_tab[64]
-#define __pyx_n_u_bytes_serialize __pyx_string_tab[65]
-#define __pyx_n_u_c __pyx_string_tab[66]
-#define __pyx_n_u_cline_in_traceback __pyx_string_tab[67]
-#define __pyx_n_u_close_db_connections __pyx_string_tab[68]
-#define __pyx_n_u_con __pyx_string_tab[69]
-#define __pyx_n_u_conn __pyx_string_tab[70]
-#define __pyx_n_u_connect __pyx_string_tab[71]
-#define __pyx_n_u_contents __pyx_string_tab[72]
-#define __pyx_n_u_create_all __pyx_string_tab[73]
-#define __pyx_n_u_create_engine __pyx_string_tab[74]
-#define __pyx_n_u_create_genesis_block __pyx_string_tab[75]
-#define __pyx_n_u_current_time_tz __pyx_string_tab[76]
-#define __pyx_n_u_cut_microseconds __pyx_string_tab[77]
-#define __pyx_n_u_data __pyx_string_tab[78]
-#define __pyx_n_u_data_digest __pyx_string_tab[79]
-#define __pyx_n_u_data_str __pyx_string_tab[80]
-#define __pyx_n_u_datetime __pyx_string_tab[81]
-#define __pyx_n_u_db __pyx_string_tab[82]
-#define __pyx_n_u_db_path __pyx_string_tab[83]
-#define __pyx_n_u_digest __pyx_string_tab[84]
-#define __pyx_n_u_digest_size __pyx_string_tab[85]
-#define __pyx_n_u_dispose __pyx_string_tab[86]
-#define __pyx_n_u_dopt_basics __pyx_string_tab[87]
-#define __pyx_n_u_dopt_basics_datetime __pyx_string_tab[88]
-#define __pyx_n_u_dopt_pollublock_blockchain __pyx_string_tab[89]
-#define __pyx_n_u_dopt_pollublock_blockchain_block __pyx_string_tab[90]
-#define __pyx_n_u_encode __pyx_string_tab[91]
-#define __pyx_n_u_enter __pyx_string_tab[92]
-#define __pyx_n_u_entries __pyx_string_tab[93]
-#define __pyx_n_u_execute __pyx_string_tab[94]
-#define __pyx_n_u_exists __pyx_string_tab[95]
-#define __pyx_n_u_exit __pyx_string_tab[96]
-#define __pyx_n_u_from_ptr __pyx_string_tab[97]
-#define __pyx_n_u_fromhex __pyx_string_tab[98]
-#define __pyx_n_u_fromtimestamp __pyx_string_tab[99]
-#define __pyx_n_u_func __pyx_string_tab[100]
-#define __pyx_n_u_func_2 __pyx_string_tab[101]
-#define __pyx_n_u_genesis_done __pyx_string_tab[102]
-#define __pyx_n_u_genesis_prev_hash __pyx_string_tab[103]
-#define __pyx_n_u_get_block __pyx_string_tab[104]
-#define __pyx_n_u_get_saving_entries __pyx_string_tab[105]
-#define __pyx_n_u_getstate __pyx_string_tab[106]
-#define __pyx_n_u_hash __pyx_string_tab[107]
-#define __pyx_n_u_hex __pyx_string_tab[108]
-#define __pyx_n_u_idx __pyx_string_tab[109]
-#define __pyx_n_u_index __pyx_string_tab[110]
-#define __pyx_n_u_insert __pyx_string_tab[111]
-#define __pyx_n_u_is_coroutine __pyx_string_tab[112]
-#define __pyx_n_u_it __pyx_string_tab[113]
-#define __pyx_n_u_items __pyx_string_tab[114]
-#define __pyx_n_u_load __pyx_string_tab[115]
-#define __pyx_n_u_main __pyx_string_tab[116]
-#define __pyx_n_u_max __pyx_string_tab[117]
-#define __pyx_n_u_max_num __pyx_string_tab[118]
-#define __pyx_n_u_max_nummber __pyx_string_tab[119]
-#define __pyx_n_u_max_value __pyx_string_tab[120]
-#define __pyx_n_u_metadata_blockchain __pyx_string_tab[121]
-#define __pyx_n_u_min_idx __pyx_string_tab[122]
-#define __pyx_n_u_min_idx_2 __pyx_string_tab[123]
-#define __pyx_n_u_module __pyx_string_tab[124]
-#define __pyx_n_u_name __pyx_string_tab[125]
-#define __pyx_n_u_new_block __pyx_string_tab[126]
-#define __pyx_n_u_new_idx __pyx_string_tab[127]
-#define __pyx_n_u_nonce __pyx_string_tab[128]
-#define __pyx_n_u_num __pyx_string_tab[129]
-#define __pyx_n_u_order_by __pyx_string_tab[130]
-#define __pyx_n_u_parent __pyx_string_tab[131]
-#define __pyx_n_u_partitions __pyx_string_tab[132]
-#define __pyx_n_u_pathlib __pyx_string_tab[133]
-#define __pyx_n_u_perform_hash __pyx_string_tab[134]
-#define __pyx_n_u_pop __pyx_string_tab[135]
-#define __pyx_n_u_prev_block __pyx_string_tab[136]
-#define __pyx_n_u_prev_hash __pyx_string_tab[137]
-#define __pyx_n_u_previous_hash __pyx_string_tab[138]
-#define __pyx_n_u_print __pyx_string_tab[139]
-#define __pyx_n_u_print_blocks __pyx_string_tab[140]
-#define __pyx_n_u_print_key_value_pair __pyx_string_tab[141]
-#define __pyx_n_u_py_block __pyx_string_tab[142]
-#define __pyx_n_u_py_bytes __pyx_string_tab[143]
-#define __pyx_n_u_py_bytes_rehashed __pyx_string_tab[144]
-#define __pyx_n_u_pyx_state __pyx_string_tab[145]
-#define __pyx_n_u_pyx_vtable __pyx_string_tab[146]
-#define __pyx_n_u_qualname __pyx_string_tab[147]
-#define __pyx_n_u_reduce __pyx_string_tab[148]
-#define __pyx_n_u_reduce_cython __pyx_string_tab[149]
-#define __pyx_n_u_reduce_ex __pyx_string_tab[150]
-#define __pyx_n_u_repr __pyx_string_tab[151]
-#define __pyx_n_u_res __pyx_string_tab[152]
-#define __pyx_n_u_resolve __pyx_string_tab[153]
-#define __pyx_n_u_result __pyx_string_tab[154]
-#define __pyx_n_u_save __pyx_string_tab[155]
-#define __pyx_n_u_scalar __pyx_string_tab[156]
-#define __pyx_n_u_select __pyx_string_tab[157]
-#define __pyx_n_u_self __pyx_string_tab[158]
-#define __pyx_n_u_serialize_dict __pyx_string_tab[159]
-#define __pyx_n_u_serialize_res __pyx_string_tab[160]
-#define __pyx_n_u_serialize_size __pyx_string_tab[161]
-#define __pyx_n_u_set_name __pyx_string_tab[162]
-#define __pyx_n_u_setdefault __pyx_string_tab[163]
-#define __pyx_n_u_setstate __pyx_string_tab[164]
-#define __pyx_n_u_setstate_cython __pyx_string_tab[165]
-#define __pyx_n_u_sql __pyx_string_tab[166]
-#define __pyx_n_u_sqlalchemy __pyx_string_tab[167]
-#define __pyx_n_u_stmt __pyx_string_tab[168]
-#define __pyx_n_u_test __pyx_string_tab[169]
-#define __pyx_n_u_timestamp __pyx_string_tab[170]
-#define __pyx_n_u_validate __pyx_string_tab[171]
-#define __pyx_n_u_values __pyx_string_tab[172]
-#define __pyx_kp_b_ __pyx_string_tab[173]
-#define __pyx_kp_b_00000000000000000000000000000000 __pyx_string_tab[174]
-#define __pyx_kp_b_iso88591_A_1D_wc_xuAV2_b_q_t1 __pyx_string_tab[175]
-#define __pyx_kp_b_iso88591_A_1_D_q_G1_D_q_D_4q_4q_q __pyx_string_tab[176]
-#define __pyx_kp_b_iso88591_A_4q_a_YgQa_t_Qa_IQ_Q_gQa_t_Qa_4 __pyx_string_tab[177]
-#define __pyx_kp_b_iso88591_A_4q_aq_q_XQc_89ARwb_dRS_IS_1A_K __pyx_string_tab[178]
-#define __pyx_kp_b_iso88591_A_4r_3d_D_AQ_D_AQ_6_A_AQ_iq_Q __pyx_string_tab[179]
-#define __pyx_kp_b_iso88591_A_4t1_aq_4z_1A_4z_T_Qd_Ja_hb_IQ __pyx_string_tab[180]
-#define __pyx_kp_b_iso88591_A_HHA __pyx_string_tab[181]
-#define __pyx_kp_b_iso88591_A_Qd_1A __pyx_string_tab[182]
-#define __pyx_kp_b_iso88591_A_T_F_c_D_4q_c_L_1_iq __pyx_string_tab[183]
-#define __pyx_kp_b_iso88591_A_a_1_83a_AQ_G5_WARuA_D_q_1_iq_1 __pyx_string_tab[184]
-#define __pyx_kp_b_iso88591_A_a_83a_q_G5_WARuA_t3a_D_q_1_q_A __pyx_string_tab[185]
-#define __pyx_kp_b_iso88591_A_a_G5_WARuA_D_q_1_uHAU_waq_1G1A __pyx_string_tab[186]
-#define __pyx_kp_b_iso88591_A_s_U_ar_q_T_gQ_4q_vQ_xq_7_2Zq __pyx_string_tab[187]
-#define __pyx_kp_b_iso88591_Q __pyx_string_tab[188]
+#define __pyx_n_u_Data_2 __pyx_string_tab[49]
+#define __pyx_n_u_Hash_2 __pyx_string_tab[50]
+#define __pyx_n_u_Index __pyx_string_tab[51]
+#define __pyx_n_u_Nonce_2 __pyx_string_tab[52]
+#define __pyx_n_u_Path __pyx_string_tab[53]
+#define __pyx_n_u_PrevHash __pyx_string_tab[54]
+#define __pyx_n_u_PyBlock __pyx_string_tab[55]
+#define __pyx_n_u_PyBlockData __pyx_string_tab[56]
+#define __pyx_n_u_PyBlock___reduce_cython __pyx_string_tab[57]
+#define __pyx_n_u_PyBlock___setstate_cython __pyx_string_tab[58]
+#define __pyx_n_u_PyBlock_as_dataclass __pyx_string_tab[59]
+#define __pyx_n_u_PyBlock_bytes_serialize __pyx_string_tab[60]
+#define __pyx_n_u_PyBlock_perform_hash __pyx_string_tab[61]
+#define __pyx_n_u_PyBlock_serialize_dict __pyx_string_tab[62]
+#define __pyx_n_u_Pyx_PyDict_NextRef __pyx_string_tab[63]
+#define __pyx_n_u_TIMEZONE_UTC __pyx_string_tab[64]
+#define __pyx_n_u_Timestamp_2 __pyx_string_tab[65]
+#define __pyx_n_u_as_dataclass __pyx_string_tab[66]
+#define __pyx_n_u_asc __pyx_string_tab[67]
+#define __pyx_n_u_asyncio_coroutines __pyx_string_tab[68]
+#define __pyx_n_u_batch __pyx_string_tab[69]
+#define __pyx_n_u_batch_size __pyx_string_tab[70]
+#define __pyx_n_u_begin __pyx_string_tab[71]
+#define __pyx_n_u_block __pyx_string_tab[72]
+#define __pyx_n_u_blocks __pyx_string_tab[73]
+#define __pyx_n_u_bytes_serialize __pyx_string_tab[74]
+#define __pyx_n_u_c __pyx_string_tab[75]
+#define __pyx_n_u_cline_in_traceback __pyx_string_tab[76]
+#define __pyx_n_u_close_db_connections __pyx_string_tab[77]
+#define __pyx_n_u_con __pyx_string_tab[78]
+#define __pyx_n_u_conn __pyx_string_tab[79]
+#define __pyx_n_u_connect __pyx_string_tab[80]
+#define __pyx_n_u_contents __pyx_string_tab[81]
+#define __pyx_n_u_create_all __pyx_string_tab[82]
+#define __pyx_n_u_create_engine __pyx_string_tab[83]
+#define __pyx_n_u_create_genesis_block __pyx_string_tab[84]
+#define __pyx_n_u_current_time_tz __pyx_string_tab[85]
+#define __pyx_n_u_cut_microseconds __pyx_string_tab[86]
+#define __pyx_n_u_data __pyx_string_tab[87]
+#define __pyx_n_u_data_digest __pyx_string_tab[88]
+#define __pyx_n_u_data_str __pyx_string_tab[89]
+#define __pyx_n_u_datetime __pyx_string_tab[90]
+#define __pyx_n_u_db __pyx_string_tab[91]
+#define __pyx_n_u_db_path __pyx_string_tab[92]
+#define __pyx_n_u_digest __pyx_string_tab[93]
+#define __pyx_n_u_digest_size __pyx_string_tab[94]
+#define __pyx_n_u_dispose __pyx_string_tab[95]
+#define __pyx_n_u_dopt_basics __pyx_string_tab[96]
+#define __pyx_n_u_dopt_basics_datetime __pyx_string_tab[97]
+#define __pyx_n_u_dopt_pollublock_blockchain __pyx_string_tab[98]
+#define __pyx_n_u_dopt_pollublock_blockchain_block __pyx_string_tab[99]
+#define __pyx_n_u_encode __pyx_string_tab[100]
+#define __pyx_n_u_enter __pyx_string_tab[101]
+#define __pyx_n_u_entries __pyx_string_tab[102]
+#define __pyx_n_u_execute __pyx_string_tab[103]
+#define __pyx_n_u_exists __pyx_string_tab[104]
+#define __pyx_n_u_exit __pyx_string_tab[105]
+#define __pyx_n_u_from_ptr __pyx_string_tab[106]
+#define __pyx_n_u_fromhex __pyx_string_tab[107]
+#define __pyx_n_u_fromtimestamp __pyx_string_tab[108]
+#define __pyx_n_u_func __pyx_string_tab[109]
+#define __pyx_n_u_func_2 __pyx_string_tab[110]
+#define __pyx_n_u_genesis_done __pyx_string_tab[111]
+#define __pyx_n_u_genesis_prev_hash __pyx_string_tab[112]
+#define __pyx_n_u_get_block __pyx_string_tab[113]
+#define __pyx_n_u_get_saving_entries __pyx_string_tab[114]
+#define __pyx_n_u_getstate __pyx_string_tab[115]
+#define __pyx_n_u_hash __pyx_string_tab[116]
+#define __pyx_n_u_hex __pyx_string_tab[117]
+#define __pyx_n_u_idx __pyx_string_tab[118]
+#define __pyx_n_u_index __pyx_string_tab[119]
+#define __pyx_n_u_insert __pyx_string_tab[120]
+#define __pyx_n_u_is_coroutine __pyx_string_tab[121]
+#define __pyx_n_u_it __pyx_string_tab[122]
+#define __pyx_n_u_items __pyx_string_tab[123]
+#define __pyx_n_u_load __pyx_string_tab[124]
+#define __pyx_n_u_main __pyx_string_tab[125]
+#define __pyx_n_u_max __pyx_string_tab[126]
+#define __pyx_n_u_max_num __pyx_string_tab[127]
+#define __pyx_n_u_max_nummber __pyx_string_tab[128]
+#define __pyx_n_u_max_value __pyx_string_tab[129]
+#define __pyx_n_u_metadata_blockchain __pyx_string_tab[130]
+#define __pyx_n_u_min_idx __pyx_string_tab[131]
+#define __pyx_n_u_min_idx_2 __pyx_string_tab[132]
+#define __pyx_n_u_module __pyx_string_tab[133]
+#define __pyx_n_u_name __pyx_string_tab[134]
+#define __pyx_n_u_new_block __pyx_string_tab[135]
+#define __pyx_n_u_new_idx __pyx_string_tab[136]
+#define __pyx_n_u_nonce __pyx_string_tab[137]
+#define __pyx_n_u_num __pyx_string_tab[138]
+#define __pyx_n_u_order_by __pyx_string_tab[139]
+#define __pyx_n_u_parent __pyx_string_tab[140]
+#define __pyx_n_u_partitions __pyx_string_tab[141]
+#define __pyx_n_u_pathlib __pyx_string_tab[142]
+#define __pyx_n_u_perform_hash __pyx_string_tab[143]
+#define __pyx_n_u_pop __pyx_string_tab[144]
+#define __pyx_n_u_prev_block __pyx_string_tab[145]
+#define __pyx_n_u_prev_hash __pyx_string_tab[146]
+#define __pyx_n_u_previous_hash __pyx_string_tab[147]
+#define __pyx_n_u_print __pyx_string_tab[148]
+#define __pyx_n_u_print_blocks __pyx_string_tab[149]
+#define __pyx_n_u_print_key_value_pair __pyx_string_tab[150]
+#define __pyx_n_u_py_block __pyx_string_tab[151]
+#define __pyx_n_u_py_bytes __pyx_string_tab[152]
+#define __pyx_n_u_py_bytes_rehashed __pyx_string_tab[153]
+#define __pyx_n_u_pyx_state __pyx_string_tab[154]
+#define __pyx_n_u_pyx_vtable __pyx_string_tab[155]
+#define __pyx_n_u_qualname __pyx_string_tab[156]
+#define __pyx_n_u_reduce __pyx_string_tab[157]
+#define __pyx_n_u_reduce_cython __pyx_string_tab[158]
+#define __pyx_n_u_reduce_ex __pyx_string_tab[159]
+#define __pyx_n_u_repr __pyx_string_tab[160]
+#define __pyx_n_u_res __pyx_string_tab[161]
+#define __pyx_n_u_resolve __pyx_string_tab[162]
+#define __pyx_n_u_result __pyx_string_tab[163]
+#define __pyx_n_u_save __pyx_string_tab[164]
+#define __pyx_n_u_scalar __pyx_string_tab[165]
+#define __pyx_n_u_select __pyx_string_tab[166]
+#define __pyx_n_u_self __pyx_string_tab[167]
+#define __pyx_n_u_serialize_dict __pyx_string_tab[168]
+#define __pyx_n_u_serialize_res __pyx_string_tab[169]
+#define __pyx_n_u_serialize_size __pyx_string_tab[170]
+#define __pyx_n_u_set_name __pyx_string_tab[171]
+#define __pyx_n_u_setdefault __pyx_string_tab[172]
+#define __pyx_n_u_setstate __pyx_string_tab[173]
+#define __pyx_n_u_setstate_cython __pyx_string_tab[174]
+#define __pyx_n_u_sql __pyx_string_tab[175]
+#define __pyx_n_u_sqlalchemy __pyx_string_tab[176]
+#define __pyx_n_u_stmt __pyx_string_tab[177]
+#define __pyx_n_u_test __pyx_string_tab[178]
+#define __pyx_n_u_timestamp __pyx_string_tab[179]
+#define __pyx_n_u_types __pyx_string_tab[180]
+#define __pyx_n_u_validate __pyx_string_tab[181]
+#define __pyx_n_u_values __pyx_string_tab[182]
+#define __pyx_kp_b_ __pyx_string_tab[183]
+#define __pyx_kp_b_00000000000000000000000000000000 __pyx_string_tab[184]
+#define __pyx_kp_b_iso88591_A_1D_wc_xuAV2_b_q_t1 __pyx_string_tab[185]
+#define __pyx_kp_b_iso88591_A_1_D_q_G1_D_q_D_4q_4q_q __pyx_string_tab[186]
+#define __pyx_kp_b_iso88591_A_4q_a_YgQa_t_Qa_IQ_Q_gQa_t_Qa_4 __pyx_string_tab[187]
+#define __pyx_kp_b_iso88591_A_4q_aq_q_XQc_89ARwb_dRS_IS_1A_K __pyx_string_tab[188]
+#define __pyx_kp_b_iso88591_A_4r_3d_D_AQ_D_AQ_6_A_AQ_iq_Q __pyx_string_tab[189]
+#define __pyx_kp_b_iso88591_A_4t1_aq_4z_1A_4z_T_Qd_Ja_hb_IQ __pyx_string_tab[190]
+#define __pyx_kp_b_iso88591_A_HHA __pyx_string_tab[191]
+#define __pyx_kp_b_iso88591_A_Qd_1A __pyx_string_tab[192]
+#define __pyx_kp_b_iso88591_A_T_F_c_D_4q_c_L_1_iq __pyx_string_tab[193]
+#define __pyx_kp_b_iso88591_A_a_1_83a_AQ_G5_WARuA_D_q_1_iq_1 __pyx_string_tab[194]
+#define __pyx_kp_b_iso88591_A_a_83a_q_G5_WARuA_t3a_D_q_1_q_A __pyx_string_tab[195]
+#define __pyx_kp_b_iso88591_A_a_G5_WARuA_D_q_1_uHAU_waq_1G1A __pyx_string_tab[196]
+#define __pyx_kp_b_iso88591_A_s_U_ar_q_T_gQ_4q_vQ_xq_7_2Zq __pyx_string_tab[197]
+#define __pyx_kp_b_iso88591_A_uL_a_d_a_T_Q_Q __pyx_string_tab[198]
+#define __pyx_kp_b_iso88591_Q __pyx_string_tab[199]
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+  __pyx_t_4 = __Pyx_PyObject_GetAttrStr(__pyx_t_3, __pyx_mstate_global->__pyx_n_u_datetime); if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 38, __pyx_L1_error)
   __Pyx_GOTREF(__pyx_t_4);
   __Pyx_DECREF(__pyx_t_3); __pyx_t_3 = 0;
   __pyx_t_2 = __pyx_t_4;
@@ -3674,20 +3686,20 @@ static uint64_t __pyx_f_26dopt_pollublock_blockchain_10blockchain_current_timest
   __pyx_t_5 = 0;
   {
     PyObject *__pyx_callargs[2 + ((CYTHON_VECTORCALL) ? 1 : 0)] = {__pyx_t_2, NULL};
-    __pyx_t_3 = __Pyx_MakeVectorcallBuilderKwds(1); if (unlikely(!__pyx_t_3)) __PYX_ERR(0, 37, __pyx_L1_error)
+    __pyx_t_3 = __Pyx_MakeVectorcallBuilderKwds(1); if (unlikely(!__pyx_t_3)) __PYX_ERR(0, 38, __pyx_L1_error)
     __Pyx_GOTREF(__pyx_t_3);
-    if (__Pyx_VectorcallBuilder_AddArg(__pyx_mstate_global->__pyx_n_u_cut_microseconds, Py_True, __pyx_t_3, __pyx_callargs+1, 0) < (0)) __PYX_ERR(0, 37, __pyx_L1_error)
+    if (__Pyx_VectorcallBuilder_AddArg(__pyx_mstate_global->__pyx_n_u_cut_microseconds, Py_True, __pyx_t_3, __pyx_callargs+1, 0) < (0)) __PYX_ERR(0, 38, __pyx_L1_error)
     __pyx_t_1 = __Pyx_Object_VectorcallMethod_CallFromBuilder((PyObject*)__pyx_mstate_global->__pyx_n_u_current_time_tz, __pyx_callargs+__pyx_t_5, (1-__pyx_t_5) | (1*__Pyx_PY_VECTORCALL_ARGUMENTS_OFFSET), __pyx_t_3);
     __Pyx_XDECREF(__pyx_t_2); __pyx_t_2 = 0;
     __Pyx_DECREF(__pyx_t_3); __pyx_t_3 = 0;
     __Pyx_DECREF(__pyx_t_4); __pyx_t_4 = 0;
-    if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 37, __pyx_L1_error)
+    if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 38, __pyx_L1_error)
     __Pyx_GOTREF(__pyx_t_1);
   }
   __pyx_v_dt = __pyx_t_1;
   __pyx_t_1 = 0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":38
+  /* "dopt_pollublock_blockchain/blockchain.pyx":39
  *     cdef uint64_t ts
  *     dt = dopt_basics.datetime.current_time_tz(cut_microseconds=True)
  *     ts = <uint64_t>int(dt.timestamp())             # <<<<<<<<<<<<<<
@@ -3701,17 +3713,17 @@ static uint64_t __pyx_f_26dopt_pollublock_blockchain_10blockchain_current_timest
     PyObject *__pyx_callargs[2] = {__pyx_t_4, NULL};
     __pyx_t_1 = __Pyx_PyObject_FastCallMethod((PyObject*)__pyx_mstate_global->__pyx_n_u_timestamp, __pyx_callargs+__pyx_t_5, (1-__pyx_t_5) | (1*__Pyx_PY_VECTORCALL_ARGUMENTS_OFFSET));
     __Pyx_XDECREF(__pyx_t_4); __pyx_t_4 = 0;
-    if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 38, __pyx_L1_error)
+    if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 39, __pyx_L1_error)
     __Pyx_GOTREF(__pyx_t_1);
   }
-  __pyx_t_4 = __Pyx_PyNumber_Int(__pyx_t_1); if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 38, __pyx_L1_error)
+  __pyx_t_4 = __Pyx_PyNumber_Int(__pyx_t_1); if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 39, __pyx_L1_error)
   __Pyx_GOTREF(__pyx_t_4);
   __Pyx_DECREF(__pyx_t_1); __pyx_t_1 = 0;
-  __pyx_t_6 = __Pyx_PyLong_As_uint64_t(__pyx_t_4); if (unlikely((__pyx_t_6 == ((uint64_t)-1)) && PyErr_Occurred())) __PYX_ERR(0, 38, __pyx_L1_error)
+  __pyx_t_6 = __Pyx_PyLong_As_uint64_t(__pyx_t_4); if (unlikely((__pyx_t_6 == ((uint64_t)-1)) && PyErr_Occurred())) __PYX_ERR(0, 39, __pyx_L1_error)
   __Pyx_DECREF(__pyx_t_4); __pyx_t_4 = 0;
   __pyx_v_ts = ((uint64_t)__pyx_t_6);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":39
+  /* "dopt_pollublock_blockchain/blockchain.pyx":40
  *     dt = dopt_basics.datetime.current_time_tz(cut_microseconds=True)
  *     ts = <uint64_t>int(dt.timestamp())
  *     return ts             # <<<<<<<<<<<<<<
@@ -3721,7 +3733,7 @@ static uint64_t __pyx_f_26dopt_pollublock_blockchain_10blockchain_current_timest
   __pyx_r = __pyx_v_ts;
   goto __pyx_L0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":35
+  /* "dopt_pollublock_blockchain/blockchain.pyx":36
  * 
  * 
  * cdef uint64_t current_timestamp_integer():             # <<<<<<<<<<<<<<
@@ -3743,7 +3755,7 @@ static uint64_t __pyx_f_26dopt_pollublock_blockchain_10blockchain_current_timest
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":42
+/* "dopt_pollublock_blockchain/blockchain.pyx":43
  * 
  * 
  * cdef int serialize_uint32(unsigned char* out, unsigned int v) except -1 nogil:             # <<<<<<<<<<<<<<
@@ -3754,7 +3766,7 @@ static uint64_t __pyx_f_26dopt_pollublock_blockchain_10blockchain_current_timest
 static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint32(unsigned char *__pyx_v_out, unsigned int __pyx_v_v) {
   int __pyx_r;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":43
+  /* "dopt_pollublock_blockchain/blockchain.pyx":44
  * 
  * cdef int serialize_uint32(unsigned char* out, unsigned int v) except -1 nogil:
  *     out[0] = (v >> 24) & 0xFF             # <<<<<<<<<<<<<<
@@ -3763,7 +3775,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint32(un
 */
   (__pyx_v_out[0]) = ((__pyx_v_v >> 24) & 0xFF);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":44
+  /* "dopt_pollublock_blockchain/blockchain.pyx":45
  * cdef int serialize_uint32(unsigned char* out, unsigned int v) except -1 nogil:
  *     out[0] = (v >> 24) & 0xFF
  *     out[1] = (v >> 16) & 0xFF             # <<<<<<<<<<<<<<
@@ -3772,7 +3784,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint32(un
 */
   (__pyx_v_out[1]) = ((__pyx_v_v >> 16) & 0xFF);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":45
+  /* "dopt_pollublock_blockchain/blockchain.pyx":46
  *     out[0] = (v >> 24) & 0xFF
  *     out[1] = (v >> 16) & 0xFF
  *     out[2] = (v >> 8)  & 0xFF             # <<<<<<<<<<<<<<
@@ -3781,7 +3793,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint32(un
 */
   (__pyx_v_out[2]) = ((__pyx_v_v >> 8) & 0xFF);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":46
+  /* "dopt_pollublock_blockchain/blockchain.pyx":47
  *     out[1] = (v >> 16) & 0xFF
  *     out[2] = (v >> 8)  & 0xFF
  *     out[3] = v & 0xFF             # <<<<<<<<<<<<<<
@@ -3790,7 +3802,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint32(un
 */
   (__pyx_v_out[3]) = (__pyx_v_v & 0xFF);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":42
+  /* "dopt_pollublock_blockchain/blockchain.pyx":43
  * 
  * 
  * cdef int serialize_uint32(unsigned char* out, unsigned int v) except -1 nogil:             # <<<<<<<<<<<<<<
@@ -3803,7 +3815,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint32(un
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":49
+/* "dopt_pollublock_blockchain/blockchain.pyx":50
  * 
  * 
  * cdef int serialize_uint64(unsigned char* out, unsigned long long v) except -1 nogil:             # <<<<<<<<<<<<<<
@@ -3814,7 +3826,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint32(un
 static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64(unsigned char *__pyx_v_out, unsigned PY_LONG_LONG __pyx_v_v) {
   int __pyx_r;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":50
+  /* "dopt_pollublock_blockchain/blockchain.pyx":51
  * 
  * cdef int serialize_uint64(unsigned char* out, unsigned long long v) except -1 nogil:
  *     out[0] = (v >> 56) & 0xFF             # <<<<<<<<<<<<<<
@@ -3823,7 +3835,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64(un
 */
   (__pyx_v_out[0]) = ((__pyx_v_v >> 56) & 0xFF);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":51
+  /* "dopt_pollublock_blockchain/blockchain.pyx":52
  * cdef int serialize_uint64(unsigned char* out, unsigned long long v) except -1 nogil:
  *     out[0] = (v >> 56) & 0xFF
  *     out[1] = (v >> 48) & 0xFF             # <<<<<<<<<<<<<<
@@ -3832,7 +3844,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64(un
 */
   (__pyx_v_out[1]) = ((__pyx_v_v >> 48) & 0xFF);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":52
+  /* "dopt_pollublock_blockchain/blockchain.pyx":53
  *     out[0] = (v >> 56) & 0xFF
  *     out[1] = (v >> 48) & 0xFF
  *     out[2] = (v >> 40) & 0xFF             # <<<<<<<<<<<<<<
@@ -3841,7 +3853,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64(un
 */
   (__pyx_v_out[2]) = ((__pyx_v_v >> 40) & 0xFF);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":53
+  /* "dopt_pollublock_blockchain/blockchain.pyx":54
  *     out[1] = (v >> 48) & 0xFF
  *     out[2] = (v >> 40) & 0xFF
  *     out[3] = (v >> 32) & 0xFF             # <<<<<<<<<<<<<<
@@ -3850,7 +3862,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64(un
 */
   (__pyx_v_out[3]) = ((__pyx_v_v >> 32) & 0xFF);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":54
+  /* "dopt_pollublock_blockchain/blockchain.pyx":55
  *     out[2] = (v >> 40) & 0xFF
  *     out[3] = (v >> 32) & 0xFF
  *     out[4] = (v >> 24) & 0xFF             # <<<<<<<<<<<<<<
@@ -3859,7 +3871,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64(un
 */
   (__pyx_v_out[4]) = ((__pyx_v_v >> 24) & 0xFF);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":55
+  /* "dopt_pollublock_blockchain/blockchain.pyx":56
  *     out[3] = (v >> 32) & 0xFF
  *     out[4] = (v >> 24) & 0xFF
  *     out[5] = (v >> 16) & 0xFF             # <<<<<<<<<<<<<<
@@ -3868,7 +3880,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64(un
 */
   (__pyx_v_out[5]) = ((__pyx_v_v >> 16) & 0xFF);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":56
+  /* "dopt_pollublock_blockchain/blockchain.pyx":57
  *     out[4] = (v >> 24) & 0xFF
  *     out[5] = (v >> 16) & 0xFF
  *     out[6] = (v >> 8)  & 0xFF             # <<<<<<<<<<<<<<
@@ -3877,7 +3889,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64(un
 */
   (__pyx_v_out[6]) = ((__pyx_v_v >> 8) & 0xFF);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":57
+  /* "dopt_pollublock_blockchain/blockchain.pyx":58
  *     out[5] = (v >> 16) & 0xFF
  *     out[6] = (v >> 8)  & 0xFF
  *     out[7] = v & 0xFF             # <<<<<<<<<<<<<<
@@ -3886,7 +3898,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64(un
 */
   (__pyx_v_out[7]) = (__pyx_v_v & 0xFF);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":49
+  /* "dopt_pollublock_blockchain/blockchain.pyx":50
  * 
  * 
  * cdef int serialize_uint64(unsigned char* out, unsigned long long v) except -1 nogil:             # <<<<<<<<<<<<<<
@@ -3899,7 +3911,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64(un
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":60
+/* "dopt_pollublock_blockchain/blockchain.pyx":61
  * 
  * 
  * cdef inline bint has_leading_zero_bits(const unsigned char *digest, int num_bits) nogil:             # <<<<<<<<<<<<<<
@@ -3917,7 +3929,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
   int __pyx_t_3;
   int __pyx_t_4;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":61
+  /* "dopt_pollublock_blockchain/blockchain.pyx":62
  * 
  * cdef inline bint has_leading_zero_bits(const unsigned char *digest, int num_bits) nogil:
  *     cdef int i, full_bytes = num_bits // 8             # <<<<<<<<<<<<<<
@@ -3926,7 +3938,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
 */
   __pyx_v_full_bytes = __Pyx_div_long(__pyx_v_num_bits, 8, 1);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":62
+  /* "dopt_pollublock_blockchain/blockchain.pyx":63
  * cdef inline bint has_leading_zero_bits(const unsigned char *digest, int num_bits) nogil:
  *     cdef int i, full_bytes = num_bits // 8
  *     cdef int rem_bits = num_bits % 8             # <<<<<<<<<<<<<<
@@ -3935,7 +3947,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
 */
   __pyx_v_rem_bits = __Pyx_mod_long(__pyx_v_num_bits, 8, 1);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":64
+  /* "dopt_pollublock_blockchain/blockchain.pyx":65
  *     cdef int rem_bits = num_bits % 8
  * 
  *     for i in range(full_bytes):             # <<<<<<<<<<<<<<
@@ -3947,7 +3959,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
   for (__pyx_t_3 = 0; __pyx_t_3 < __pyx_t_2; __pyx_t_3+=1) {
     __pyx_v_i = __pyx_t_3;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":65
+    /* "dopt_pollublock_blockchain/blockchain.pyx":66
  * 
  *     for i in range(full_bytes):
  *         if digest[i] != 0:             # <<<<<<<<<<<<<<
@@ -3957,7 +3969,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
     __pyx_t_4 = ((__pyx_v_digest[__pyx_v_i]) != 0);
     if (__pyx_t_4) {
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":66
+      /* "dopt_pollublock_blockchain/blockchain.pyx":67
  *     for i in range(full_bytes):
  *         if digest[i] != 0:
  *             return False             # <<<<<<<<<<<<<<
@@ -3967,7 +3979,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
       __pyx_r = 0;
       goto __pyx_L0;
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":65
+      /* "dopt_pollublock_blockchain/blockchain.pyx":66
  * 
  *     for i in range(full_bytes):
  *         if digest[i] != 0:             # <<<<<<<<<<<<<<
@@ -3977,7 +3989,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
     }
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":68
+  /* "dopt_pollublock_blockchain/blockchain.pyx":69
  *             return False
  * 
  *     if rem_bits:             # <<<<<<<<<<<<<<
@@ -3987,7 +3999,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
   __pyx_t_4 = (__pyx_v_rem_bits != 0);
   if (__pyx_t_4) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":69
+    /* "dopt_pollublock_blockchain/blockchain.pyx":70
  * 
  *     if rem_bits:
  *         if digest[full_bytes] >> (8 - rem_bits) != 0:             # <<<<<<<<<<<<<<
@@ -3997,7 +4009,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
     __pyx_t_4 = (((__pyx_v_digest[__pyx_v_full_bytes]) >> (8 - __pyx_v_rem_bits)) != 0);
     if (__pyx_t_4) {
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":70
+      /* "dopt_pollublock_blockchain/blockchain.pyx":71
  *     if rem_bits:
  *         if digest[full_bytes] >> (8 - rem_bits) != 0:
  *             return False             # <<<<<<<<<<<<<<
@@ -4007,7 +4019,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
       __pyx_r = 0;
       goto __pyx_L0;
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":69
+      /* "dopt_pollublock_blockchain/blockchain.pyx":70
  * 
  *     if rem_bits:
  *         if digest[full_bytes] >> (8 - rem_bits) != 0:             # <<<<<<<<<<<<<<
@@ -4016,7 +4028,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
 */
     }
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":68
+    /* "dopt_pollublock_blockchain/blockchain.pyx":69
  *             return False
  * 
  *     if rem_bits:             # <<<<<<<<<<<<<<
@@ -4025,7 +4037,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":72
+  /* "dopt_pollublock_blockchain/blockchain.pyx":73
  *             return False
  * 
  *     return True             # <<<<<<<<<<<<<<
@@ -4035,7 +4047,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
   __pyx_r = 1;
   goto __pyx_L0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":60
+  /* "dopt_pollublock_blockchain/blockchain.pyx":61
  * 
  * 
  * cdef inline bint has_leading_zero_bits(const unsigned char *digest, int num_bits) nogil:             # <<<<<<<<<<<<<<
@@ -4048,7 +4060,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":75
+/* "dopt_pollublock_blockchain/blockchain.pyx":76
  * 
  * 
  * cdef inline bint has_leading_zero_bytes(const unsigned char *digest, int num_bytes) nogil:             # <<<<<<<<<<<<<<
@@ -4066,7 +4078,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
   int __pyx_t_3;
   int __pyx_t_4;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":76
+  /* "dopt_pollublock_blockchain/blockchain.pyx":77
  * 
  * cdef inline bint has_leading_zero_bytes(const unsigned char *digest, int num_bytes) nogil:
  *     cdef int i, full_bytes = num_bytes // 8             # <<<<<<<<<<<<<<
@@ -4075,7 +4087,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
 */
   __pyx_v_full_bytes = __Pyx_div_long(__pyx_v_num_bytes, 8, 1);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":77
+  /* "dopt_pollublock_blockchain/blockchain.pyx":78
  * cdef inline bint has_leading_zero_bytes(const unsigned char *digest, int num_bytes) nogil:
  *     cdef int i, full_bytes = num_bytes // 8
  *     cdef int rem_bits = num_bytes % 8             # <<<<<<<<<<<<<<
@@ -4084,7 +4096,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
 */
   __pyx_v_rem_bits = __Pyx_mod_long(__pyx_v_num_bytes, 8, 1);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":79
+  /* "dopt_pollublock_blockchain/blockchain.pyx":80
  *     cdef int rem_bits = num_bytes % 8
  * 
  *     for i in range(num_bytes):             # <<<<<<<<<<<<<<
@@ -4096,7 +4108,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
   for (__pyx_t_3 = 0; __pyx_t_3 < __pyx_t_2; __pyx_t_3+=1) {
     __pyx_v_i = __pyx_t_3;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":80
+    /* "dopt_pollublock_blockchain/blockchain.pyx":81
  * 
  *     for i in range(num_bytes):
  *         if digest[i] != 0:             # <<<<<<<<<<<<<<
@@ -4106,7 +4118,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
     __pyx_t_4 = ((__pyx_v_digest[__pyx_v_i]) != 0);
     if (__pyx_t_4) {
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":81
+      /* "dopt_pollublock_blockchain/blockchain.pyx":82
  *     for i in range(num_bytes):
  *         if digest[i] != 0:
  *             return False             # <<<<<<<<<<<<<<
@@ -4116,7 +4128,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
       __pyx_r = 0;
       goto __pyx_L0;
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":80
+      /* "dopt_pollublock_blockchain/blockchain.pyx":81
  * 
  *     for i in range(num_bytes):
  *         if digest[i] != 0:             # <<<<<<<<<<<<<<
@@ -4126,7 +4138,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
     }
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":83
+  /* "dopt_pollublock_blockchain/blockchain.pyx":84
  *             return False
  * 
  *     return True             # <<<<<<<<<<<<<<
@@ -4136,7 +4148,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
   __pyx_r = 1;
   goto __pyx_L0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":75
+  /* "dopt_pollublock_blockchain/blockchain.pyx":76
  * 
  * 
  * cdef inline bint has_leading_zero_bytes(const unsigned char *digest, int num_bytes) nogil:             # <<<<<<<<<<<<<<
@@ -4149,7 +4161,7 @@ static CYTHON_INLINE int __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_l
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":91
+/* "dopt_pollublock_blockchain/blockchain.pyx":92
  *         bint ptr_owner
  * 
  *     def __cinit__(self,             # <<<<<<<<<<<<<<
@@ -4183,36 +4195,36 @@ static int __pyx_pw_26dopt_pollublock_blockchain_10blockchain_7PyBlock_1__cinit_
   {
     PyObject ** const __pyx_pyargnames[] = {&__pyx_mstate_global->__pyx_n_u_index,&__pyx_mstate_global->__pyx_n_u_nonce,&__pyx_mstate_global->__pyx_n_u_data,&__pyx_mstate_global->__pyx_n_u_previous_hash,&__pyx_mstate_global->__pyx_n_u_from_ptr,0};
     const Py_ssize_t __pyx_kwds_len = (__pyx_kwds) ? __Pyx_NumKwargs_VARARGS(__pyx_kwds) : 0;
-    if (unlikely(__pyx_kwds_len) < 0) __PYX_ERR(0, 91, __pyx_L3_error)
+    if (unlikely(__pyx_kwds_len) < 0) __PYX_ERR(0, 92, __pyx_L3_error)
     if (__pyx_kwds_len > 0) {
       switch (__pyx_nargs) {
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-        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[4])) __PYX_ERR(0, 91, __pyx_L3_error)
+        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[4])) __PYX_ERR(0, 92, __pyx_L3_error)
         CYTHON_FALLTHROUGH;
         case  4:
         values[3] = __Pyx_ArgRef_VARARGS(__pyx_args, 3);
-        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[3])) __PYX_ERR(0, 91, __pyx_L3_error)
+        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[3])) __PYX_ERR(0, 92, __pyx_L3_error)
         CYTHON_FALLTHROUGH;
         case  3:
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-        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[2])) __PYX_ERR(0, 91, __pyx_L3_error)
+        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[2])) __PYX_ERR(0, 92, __pyx_L3_error)
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-        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[1])) __PYX_ERR(0, 91, __pyx_L3_error)
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         CYTHON_FALLTHROUGH;
         case  1:
         values[0] = __Pyx_ArgRef_VARARGS(__pyx_args, 0);
-        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[0])) __PYX_ERR(0, 91, __pyx_L3_error)
+        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[0])) __PYX_ERR(0, 92, __pyx_L3_error)
         CYTHON_FALLTHROUGH;
         case  0: break;
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       const Py_ssize_t kwd_pos_args = __pyx_nargs;
-      if (__Pyx_ParseKeywords(__pyx_kwds, __pyx_kwvalues, __pyx_pyargnames, 0, values, kwd_pos_args, __pyx_kwds_len, "__cinit__", 0) < (0)) __PYX_ERR(0, 91, __pyx_L3_error)
+      if (__Pyx_ParseKeywords(__pyx_kwds, __pyx_kwvalues, __pyx_pyargnames, 0, values, kwd_pos_args, __pyx_kwds_len, "__cinit__", 0) < (0)) __PYX_ERR(0, 92, __pyx_L3_error)
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":96
+      /* "dopt_pollublock_blockchain/blockchain.pyx":97
  *         data,
  *         previous_hash,
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@@ -4221,23 +4233,23 @@ static int __pyx_pw_26dopt_pollublock_blockchain_10blockchain_7PyBlock_1__cinit_
 */
       if (!values[4]) values[4] = __Pyx_NewRef(((PyObject *)Py_False));
       for (Py_ssize_t i = __pyx_nargs; i < 4; i++) {
-        if (unlikely(!values[i])) { __Pyx_RaiseArgtupleInvalid("__cinit__", 0, 4, 5, i); __PYX_ERR(0, 91, __pyx_L3_error) }
+        if (unlikely(!values[i])) { __Pyx_RaiseArgtupleInvalid("__cinit__", 0, 4, 5, i); __PYX_ERR(0, 92, __pyx_L3_error) }
       }
     } else {
       switch (__pyx_nargs) {
         case  5:
         values[4] = __Pyx_ArgRef_VARARGS(__pyx_args, 4);
-        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[4])) __PYX_ERR(0, 91, __pyx_L3_error)
+        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[4])) __PYX_ERR(0, 92, __pyx_L3_error)
         CYTHON_FALLTHROUGH;
         case  4:
         values[3] = __Pyx_ArgRef_VARARGS(__pyx_args, 3);
-        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[3])) __PYX_ERR(0, 91, __pyx_L3_error)
+        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[3])) __PYX_ERR(0, 92, __pyx_L3_error)
         values[2] = __Pyx_ArgRef_VARARGS(__pyx_args, 2);
-        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[2])) __PYX_ERR(0, 91, __pyx_L3_error)
+        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[2])) __PYX_ERR(0, 92, __pyx_L3_error)
         values[1] = __Pyx_ArgRef_VARARGS(__pyx_args, 1);
-        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[1])) __PYX_ERR(0, 91, __pyx_L3_error)
+        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[1])) __PYX_ERR(0, 92, __pyx_L3_error)
         values[0] = __Pyx_ArgRef_VARARGS(__pyx_args, 0);
-        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[0])) __PYX_ERR(0, 91, __pyx_L3_error)
+        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[0])) __PYX_ERR(0, 92, __pyx_L3_error)
         break;
         default: goto __pyx_L5_argtuple_error;
       }
@@ -4251,7 +4263,7 @@ static int __pyx_pw_26dopt_pollublock_blockchain_10blockchain_7PyBlock_1__cinit_
   }
   goto __pyx_L6_skip;
   __pyx_L5_argtuple_error:;
-  __Pyx_RaiseArgtupleInvalid("__cinit__", 0, 4, 5, __pyx_nargs); __PYX_ERR(0, 91, __pyx_L3_error)
+  __Pyx_RaiseArgtupleInvalid("__cinit__", 0, 4, 5, __pyx_nargs); __PYX_ERR(0, 92, __pyx_L3_error)
   __pyx_L6_skip:;
   goto __pyx_L4_argument_unpacking_done;
   __pyx_L3_error:;
@@ -4264,7 +4276,7 @@ static int __pyx_pw_26dopt_pollublock_blockchain_10blockchain_7PyBlock_1__cinit_
   __pyx_L4_argument_unpacking_done:;
   __pyx_r = __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock___cinit__(((struct __pyx_obj_26dopt_pollublock_blockchain_10blockchain_PyBlock *)__pyx_v_self), __pyx_v_index, __pyx_v_nonce, __pyx_v_data, __pyx_v_previous_hash, __pyx_v_from_ptr);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":91
+  /* "dopt_pollublock_blockchain/blockchain.pyx":92
  *         bint ptr_owner
  * 
  *     def __cinit__(self,             # <<<<<<<<<<<<<<
@@ -4300,7 +4312,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock___cinit__
   int __pyx_clineno = 0;
   __Pyx_RefNannySetupContext("__cinit__", 0);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":98
+  /* "dopt_pollublock_blockchain/blockchain.pyx":99
  *         from_ptr=False,
  *     ):
  *         self.ptr_owner = False             # <<<<<<<<<<<<<<
@@ -4309,45 +4321,45 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock___cinit__
 */
   __pyx_v_self->ptr_owner = 0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":99
+  /* "dopt_pollublock_blockchain/blockchain.pyx":100
  *     ):
  *         self.ptr_owner = False
  *         if not from_ptr:             # <<<<<<<<<<<<<<
  *             self.BlockC = new Block(
  *                 index,
 */
-  __pyx_t_1 = __Pyx_PyObject_IsTrue(__pyx_v_from_ptr); if (unlikely((__pyx_t_1 < 0))) __PYX_ERR(0, 99, __pyx_L1_error)
+  __pyx_t_1 = __Pyx_PyObject_IsTrue(__pyx_v_from_ptr); if (unlikely((__pyx_t_1 < 0))) __PYX_ERR(0, 100, __pyx_L1_error)
   __pyx_t_2 = (!__pyx_t_1);
   if (__pyx_t_2) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":101
+    /* "dopt_pollublock_blockchain/blockchain.pyx":102
  *         if not from_ptr:
  *             self.BlockC = new Block(
  *                 index,             # <<<<<<<<<<<<<<
  *                 current_timestamp_integer(),
  *                 nonce,
 */
-    __pyx_t_3 = __Pyx_PyLong_As_uint64_t(__pyx_v_index); if (unlikely((__pyx_t_3 == ((uint64_t)-1)) && PyErr_Occurred())) __PYX_ERR(0, 101, __pyx_L1_error)
+    __pyx_t_3 = __Pyx_PyLong_As_uint64_t(__pyx_v_index); if (unlikely((__pyx_t_3 == ((uint64_t)-1)) && PyErr_Occurred())) __PYX_ERR(0, 102, __pyx_L1_error)
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":102
+    /* "dopt_pollublock_blockchain/blockchain.pyx":103
  *             self.BlockC = new Block(
  *                 index,
  *                 current_timestamp_integer(),             # <<<<<<<<<<<<<<
  *                 nonce,
  *                 data.encode("UTF-8"),
 */
-    __pyx_t_4 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_current_timestamp_integer(); if (unlikely(__pyx_t_4 == ((uint64_t)-1LL) && PyErr_Occurred())) __PYX_ERR(0, 102, __pyx_L1_error)
+    __pyx_t_4 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_current_timestamp_integer(); if (unlikely(__pyx_t_4 == ((uint64_t)-1LL) && PyErr_Occurred())) __PYX_ERR(0, 103, __pyx_L1_error)
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":103
+    /* "dopt_pollublock_blockchain/blockchain.pyx":104
  *                 index,
  *                 current_timestamp_integer(),
  *                 nonce,             # <<<<<<<<<<<<<<
  *                 data.encode("UTF-8"),
  *                 previous_hash.encode("UTF-8"),
 */
-    __pyx_t_5 = __Pyx_PyLong_As_uint64_t(__pyx_v_nonce); if (unlikely((__pyx_t_5 == ((uint64_t)-1)) && PyErr_Occurred())) __PYX_ERR(0, 103, __pyx_L1_error)
+    __pyx_t_5 = __Pyx_PyLong_As_uint64_t(__pyx_v_nonce); if (unlikely((__pyx_t_5 == ((uint64_t)-1)) && PyErr_Occurred())) __PYX_ERR(0, 104, __pyx_L1_error)
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":104
+    /* "dopt_pollublock_blockchain/blockchain.pyx":105
  *                 current_timestamp_integer(),
  *                 nonce,
  *                 data.encode("UTF-8"),             # <<<<<<<<<<<<<<
@@ -4361,13 +4373,13 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock___cinit__
       PyObject *__pyx_callargs[2] = {__pyx_t_7, __pyx_mstate_global->__pyx_kp_u_UTF_8};
       __pyx_t_6 = __Pyx_PyObject_FastCallMethod((PyObject*)__pyx_mstate_global->__pyx_n_u_encode, __pyx_callargs+__pyx_t_8, (2-__pyx_t_8) | (1*__Pyx_PY_VECTORCALL_ARGUMENTS_OFFSET));
       __Pyx_XDECREF(__pyx_t_7); __pyx_t_7 = 0;
-      if (unlikely(!__pyx_t_6)) __PYX_ERR(0, 104, __pyx_L1_error)
+      if (unlikely(!__pyx_t_6)) __PYX_ERR(0, 105, __pyx_L1_error)
       __Pyx_GOTREF(__pyx_t_6);
     }
-    __pyx_t_9 = __pyx_convert_string_from_py_6libcpp_6string_std__in_string(__pyx_t_6); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 104, __pyx_L1_error)
+    __pyx_t_9 = __pyx_convert_string_from_py_6libcpp_6string_std__in_string(__pyx_t_6); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 105, __pyx_L1_error)
     __Pyx_DECREF(__pyx_t_6); __pyx_t_6 = 0;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":105
+    /* "dopt_pollublock_blockchain/blockchain.pyx":106
  *                 nonce,
  *                 data.encode("UTF-8"),
  *                 previous_hash.encode("UTF-8"),             # <<<<<<<<<<<<<<
@@ -4381,22 +4393,22 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock___cinit__
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       __Pyx_XDECREF(__pyx_t_7); __pyx_t_7 = 0;
-      if (unlikely(!__pyx_t_6)) __PYX_ERR(0, 105, __pyx_L1_error)
+      if (unlikely(!__pyx_t_6)) __PYX_ERR(0, 106, __pyx_L1_error)
       __Pyx_GOTREF(__pyx_t_6);
     }
-    __pyx_t_10 = __pyx_convert_string_from_py_6libcpp_6string_std__in_string(__pyx_t_6); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 105, __pyx_L1_error)
+    __pyx_t_10 = __pyx_convert_string_from_py_6libcpp_6string_std__in_string(__pyx_t_6); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 106, __pyx_L1_error)
     __Pyx_DECREF(__pyx_t_6); __pyx_t_6 = 0;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":106
+    /* "dopt_pollublock_blockchain/blockchain.pyx":107
  *                 data.encode("UTF-8"),
  *                 previous_hash.encode("UTF-8"),
  *                 "".encode("UTF-8"),             # <<<<<<<<<<<<<<
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  *             if self.BlockC is NULL:
 */
-    __pyx_t_11 = __pyx_convert_string_from_py_6libcpp_6string_std__in_string(__pyx_mstate_global->__pyx_kp_b_); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 106, __pyx_L1_error)
+    __pyx_t_11 = __pyx_convert_string_from_py_6libcpp_6string_std__in_string(__pyx_mstate_global->__pyx_kp_b_); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 107, __pyx_L1_error)
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":100
+    /* "dopt_pollublock_blockchain/blockchain.pyx":101
  *         self.ptr_owner = False
  *         if not from_ptr:
  *             self.BlockC = new Block(             # <<<<<<<<<<<<<<
@@ -4407,11 +4419,11 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock___cinit__
       __pyx_t_12 = new ::Block(__pyx_t_3, __pyx_t_4, __pyx_t_5, __pyx_t_9, __pyx_t_10, __pyx_t_11);
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       __Pyx_CppExn2PyErr();
-      __PYX_ERR(0, 100, __pyx_L1_error)
+      __PYX_ERR(0, 101, __pyx_L1_error)
     }
     __pyx_v_self->BlockC = __pyx_t_12;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":108
+    /* "dopt_pollublock_blockchain/blockchain.pyx":109
  *                 "".encode("UTF-8"),
  *             )
  *             if self.BlockC is NULL:             # <<<<<<<<<<<<<<
@@ -4421,16 +4433,16 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock___cinit__
     __pyx_t_2 = (__pyx_v_self->BlockC == NULL);
     if (unlikely(__pyx_t_2)) {
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":109
+      /* "dopt_pollublock_blockchain/blockchain.pyx":110
  *             )
  *             if self.BlockC is NULL:
  *                 raise MemoryError()             # <<<<<<<<<<<<<<
  * 
  *             self.ptr_owner = True
 */
-      PyErr_NoMemory(); __PYX_ERR(0, 109, __pyx_L1_error)
+      PyErr_NoMemory(); __PYX_ERR(0, 110, __pyx_L1_error)
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":108
+      /* "dopt_pollublock_blockchain/blockchain.pyx":109
  *                 "".encode("UTF-8"),
  *             )
  *             if self.BlockC is NULL:             # <<<<<<<<<<<<<<
@@ -4439,7 +4451,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock___cinit__
 */
     }
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":111
+    /* "dopt_pollublock_blockchain/blockchain.pyx":112
  *                 raise MemoryError()
  * 
  *             self.ptr_owner = True             # <<<<<<<<<<<<<<
@@ -4448,7 +4460,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock___cinit__
 */
     __pyx_v_self->ptr_owner = 1;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":99
+    /* "dopt_pollublock_blockchain/blockchain.pyx":100
  *     ):
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  *         if not from_ptr:             # <<<<<<<<<<<<<<
@@ -4457,7 +4469,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock___cinit__
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":91
+  /* "dopt_pollublock_blockchain/blockchain.pyx":92
  *         bint ptr_owner
  * 
  *     def __cinit__(self,             # <<<<<<<<<<<<<<
@@ -4478,7 +4490,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock___cinit__
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":113
+/* "dopt_pollublock_blockchain/blockchain.pyx":114
  *             self.ptr_owner = True
  * 
  *     def __init__(self, *args, **kwargs):             # <<<<<<<<<<<<<<
@@ -4526,7 +4538,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_2__init__
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":116
+/* "dopt_pollublock_blockchain/blockchain.pyx":117
  *         pass
  * 
  *     def __dealloc__(self):             # <<<<<<<<<<<<<<
@@ -4551,7 +4563,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_4__deall
   int __pyx_t_1;
   int __pyx_t_2;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":117
+  /* "dopt_pollublock_blockchain/blockchain.pyx":118
  * 
  *     def __dealloc__(self):
  *         if self.BlockC is not NULL and self.ptr_owner is True:             # <<<<<<<<<<<<<<
@@ -4569,7 +4581,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_4__deall
   __pyx_L4_bool_binop_done:;
   if (__pyx_t_1) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":118
+    /* "dopt_pollublock_blockchain/blockchain.pyx":119
  *     def __dealloc__(self):
  *         if self.BlockC is not NULL and self.ptr_owner is True:
  *             del self.BlockC             # <<<<<<<<<<<<<<
@@ -4578,7 +4590,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_4__deall
 */
     delete __pyx_v_self->BlockC;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":119
+    /* "dopt_pollublock_blockchain/blockchain.pyx":120
  *         if self.BlockC is not NULL and self.ptr_owner is True:
  *             del self.BlockC
  *             self.BlockC = NULL             # <<<<<<<<<<<<<<
@@ -4587,7 +4599,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_7PyBlock_4__deall
 */
     __pyx_v_self->BlockC = NULL;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":117
+    /* "dopt_pollublock_blockchain/blockchain.pyx":118
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   __pyx_t_1 = (__pyx_v_buf == NULL);
   if (__pyx_t_1) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":224
+    /* "dopt_pollublock_blockchain/blockchain.pyx":235
  * 
  *     if buf is NULL:
  *         return NULL             # <<<<<<<<<<<<<<
@@ -6252,7 +6474,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_bytes_se
     __pyx_r = NULL;
     goto __pyx_L0;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":223
+    /* "dopt_pollublock_blockchain/blockchain.pyx":234
  *     buf = <unsigned char*>malloc(size[0] * sizeof(unsigned char))
  * 
  *     if buf is NULL:             # <<<<<<<<<<<<<<
@@ -6261,16 +6483,16 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_bytes_se
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":226
+  /* "dopt_pollublock_blockchain/blockchain.pyx":237
  *         return NULL
  * 
  *     serialize_uint64(buf + pos, block.index)             # <<<<<<<<<<<<<<
  *     pos += 8
  *     serialize_uint64(buf + pos, block.timestamp)
 */
-  __pyx_t_2 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64((__pyx_v_buf + __pyx_v_pos), __pyx_v_block->index); if (unlikely(__pyx_t_2 == ((int)-1))) __PYX_ERR(0, 226, __pyx_L1_error)
+  __pyx_t_2 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64((__pyx_v_buf + __pyx_v_pos), __pyx_v_block->index); if (unlikely(__pyx_t_2 == ((int)-1))) __PYX_ERR(0, 237, __pyx_L1_error)
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":227
+  /* "dopt_pollublock_blockchain/blockchain.pyx":238
  * 
  *     serialize_uint64(buf + pos, block.index)
  *     pos += 8             # <<<<<<<<<<<<<<
@@ -6279,16 +6501,16 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_bytes_se
 */
   __pyx_v_pos = (__pyx_v_pos + 8);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":228
+  /* "dopt_pollublock_blockchain/blockchain.pyx":239
  *     serialize_uint64(buf + pos, block.index)
  *     pos += 8
  *     serialize_uint64(buf + pos, block.timestamp)             # <<<<<<<<<<<<<<
  *     pos += 8
  *     serialize_uint64(buf + pos, block.nonce)
 */
-  __pyx_t_2 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64((__pyx_v_buf + __pyx_v_pos), __pyx_v_block->timestamp); if (unlikely(__pyx_t_2 == ((int)-1))) __PYX_ERR(0, 228, __pyx_L1_error)
+  __pyx_t_2 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64((__pyx_v_buf + __pyx_v_pos), __pyx_v_block->timestamp); if (unlikely(__pyx_t_2 == ((int)-1))) __PYX_ERR(0, 239, __pyx_L1_error)
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":229
+  /* "dopt_pollublock_blockchain/blockchain.pyx":240
  *     pos += 8
  *     serialize_uint64(buf + pos, block.timestamp)
  *     pos += 8             # <<<<<<<<<<<<<<
@@ -6297,16 +6519,16 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_bytes_se
 */
   __pyx_v_pos = (__pyx_v_pos + 8);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":230
+  /* "dopt_pollublock_blockchain/blockchain.pyx":241
  *     serialize_uint64(buf + pos, block.timestamp)
  *     pos += 8
  *     serialize_uint64(buf + pos, block.nonce)             # <<<<<<<<<<<<<<
  *     pos += 8
  *     # Copy data
 */
-  __pyx_t_2 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64((__pyx_v_buf + __pyx_v_pos), __pyx_v_block->nonce); if (unlikely(__pyx_t_2 == ((int)-1))) __PYX_ERR(0, 230, __pyx_L1_error)
+  __pyx_t_2 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64((__pyx_v_buf + __pyx_v_pos), __pyx_v_block->nonce); if (unlikely(__pyx_t_2 == ((int)-1))) __PYX_ERR(0, 241, __pyx_L1_error)
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":231
+  /* "dopt_pollublock_blockchain/blockchain.pyx":242
  *     pos += 8
  *     serialize_uint64(buf + pos, block.nonce)
  *     pos += 8             # <<<<<<<<<<<<<<
@@ -6315,7 +6537,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_bytes_se
 */
   __pyx_v_pos = (__pyx_v_pos + 8);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":233
+  /* "dopt_pollublock_blockchain/blockchain.pyx":244
  *     pos += 8
  *     # Copy data
  *     memcpy(             # <<<<<<<<<<<<<<
@@ -6324,7 +6546,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_bytes_se
 */
   (void)(memcpy((__pyx_v_buf + __pyx_v_pos), __pyx_v_block->data.c_str(), __pyx_v_block->data.size()));
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":238
+  /* "dopt_pollublock_blockchain/blockchain.pyx":249
  *         block.data.size(),
  *     )
  *     pos += block.data.size()             # <<<<<<<<<<<<<<
@@ -6333,7 +6555,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_bytes_se
 */
   __pyx_v_pos = (__pyx_v_pos + __pyx_v_block->data.size());
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":240
+  /* "dopt_pollublock_blockchain/blockchain.pyx":251
  *     pos += block.data.size()
  *     # Copy prev_hash
  *     memcpy(             # <<<<<<<<<<<<<<
@@ -6342,7 +6564,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_bytes_se
 */
   (void)(memcpy((__pyx_v_buf + __pyx_v_pos), __pyx_v_block->prev_hash.c_str(), __pyx_v_block->prev_hash.size()));
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":245
+  /* "dopt_pollublock_blockchain/blockchain.pyx":256
  *         block.prev_hash.size(),
  *     )
  *     pos += block.prev_hash.size()             # <<<<<<<<<<<<<<
@@ -6351,7 +6573,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_bytes_se
 */
   __pyx_v_pos = (__pyx_v_pos + __pyx_v_block->prev_hash.size());
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":247
+  /* "dopt_pollublock_blockchain/blockchain.pyx":258
  *     pos += block.prev_hash.size()
  * 
  *     return buf             # <<<<<<<<<<<<<<
@@ -6361,7 +6583,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_bytes_se
   __pyx_r = __pyx_v_buf;
   goto __pyx_L0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":209
+  /* "dopt_pollublock_blockchain/blockchain.pyx":220
  * 
  * 
  * cdef unsigned char* bytes_serialize_c(Block *block, size_t *size) nogil:             # <<<<<<<<<<<<<<
@@ -6379,7 +6601,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_bytes_se
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":249
+/* "dopt_pollublock_blockchain/blockchain.pyx":260
  *     return buf
  * 
  * cdef unsigned char* SHA256_digest(const void *data, size_t data_size, size_t *digest_size) nogil:             # <<<<<<<<<<<<<<
@@ -6396,7 +6618,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
   unsigned char *__pyx_r;
   int __pyx_t_1;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":250
+  /* "dopt_pollublock_blockchain/blockchain.pyx":261
  * 
  * cdef unsigned char* SHA256_digest(const void *data, size_t data_size, size_t *digest_size) nogil:
  *     cdef ossl.EVP_MD_CTX *ctx = ossl.EVP_MD_CTX_new()             # <<<<<<<<<<<<<<
@@ -6405,7 +6627,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
 */
   __pyx_v_ctx = EVP_MD_CTX_new();
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":251
+  /* "dopt_pollublock_blockchain/blockchain.pyx":262
  * cdef unsigned char* SHA256_digest(const void *data, size_t data_size, size_t *digest_size) nogil:
  *     cdef ossl.EVP_MD_CTX *ctx = ossl.EVP_MD_CTX_new()
  *     if ctx is NULL:             # <<<<<<<<<<<<<<
@@ -6415,7 +6637,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
   __pyx_t_1 = (__pyx_v_ctx == NULL);
   if (__pyx_t_1) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":252
+    /* "dopt_pollublock_blockchain/blockchain.pyx":263
  *     cdef ossl.EVP_MD_CTX *ctx = ossl.EVP_MD_CTX_new()
  *     if ctx is NULL:
  *         return NULL             # <<<<<<<<<<<<<<
@@ -6425,7 +6647,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
     __pyx_r = NULL;
     goto __pyx_L0;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":251
+    /* "dopt_pollublock_blockchain/blockchain.pyx":262
  * cdef unsigned char* SHA256_digest(const void *data, size_t data_size, size_t *digest_size) nogil:
  *     cdef ossl.EVP_MD_CTX *ctx = ossl.EVP_MD_CTX_new()
  *     if ctx is NULL:             # <<<<<<<<<<<<<<
@@ -6434,7 +6656,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":253
+  /* "dopt_pollublock_blockchain/blockchain.pyx":264
  *     if ctx is NULL:
  *         return NULL
  *     cdef const ossl.EVP_MD *algo = ossl.EVP_sha256()             # <<<<<<<<<<<<<<
@@ -6443,7 +6665,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
 */
   __pyx_v_algo = EVP_sha256();
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":254
+  /* "dopt_pollublock_blockchain/blockchain.pyx":265
  *         return NULL
  *     cdef const ossl.EVP_MD *algo = ossl.EVP_sha256()
  *     if algo is NULL:             # <<<<<<<<<<<<<<
@@ -6453,7 +6675,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
   __pyx_t_1 = (__pyx_v_algo == NULL);
   if (__pyx_t_1) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":255
+    /* "dopt_pollublock_blockchain/blockchain.pyx":266
  *     cdef const ossl.EVP_MD *algo = ossl.EVP_sha256()
  *     if algo is NULL:
  *         return NULL             # <<<<<<<<<<<<<<
@@ -6463,7 +6685,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
     __pyx_r = NULL;
     goto __pyx_L0;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":254
+    /* "dopt_pollublock_blockchain/blockchain.pyx":265
  *         return NULL
  *     cdef const ossl.EVP_MD *algo = ossl.EVP_sha256()
  *     if algo is NULL:             # <<<<<<<<<<<<<<
@@ -6472,7 +6694,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":262
+  /* "dopt_pollublock_blockchain/blockchain.pyx":273
  *         unsigned int digest_len
  * 
  *     dig_buff_len = <size_t>ossl.EVP_MD_size(algo)             # <<<<<<<<<<<<<<
@@ -6481,7 +6703,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
 */
   __pyx_v_dig_buff_len = ((size_t)EVP_MD_size(__pyx_v_algo));
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":263
+  /* "dopt_pollublock_blockchain/blockchain.pyx":274
  * 
  *     dig_buff_len = <size_t>ossl.EVP_MD_size(algo)
  *     digest_size[0] = dig_buff_len             # <<<<<<<<<<<<<<
@@ -6490,7 +6712,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
 */
   (__pyx_v_digest_size[0]) = __pyx_v_dig_buff_len;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":264
+  /* "dopt_pollublock_blockchain/blockchain.pyx":275
  *     dig_buff_len = <size_t>ossl.EVP_MD_size(algo)
  *     digest_size[0] = dig_buff_len
  *     digest = <unsigned char*>malloc(dig_buff_len * sizeof(unsigned char))             # <<<<<<<<<<<<<<
@@ -6499,7 +6721,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
 */
   __pyx_v_digest = ((unsigned char *)malloc((__pyx_v_dig_buff_len * (sizeof(unsigned char)))));
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":265
+  /* "dopt_pollublock_blockchain/blockchain.pyx":276
  *     digest_size[0] = dig_buff_len
  *     digest = <unsigned char*>malloc(dig_buff_len * sizeof(unsigned char))
  *     ossl.EVP_DigestInit_ex(ctx, algo, NULL)             # <<<<<<<<<<<<<<
@@ -6508,7 +6730,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
 */
   (void)(EVP_DigestInit_ex(__pyx_v_ctx, __pyx_v_algo, NULL));
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":266
+  /* "dopt_pollublock_blockchain/blockchain.pyx":277
  *     digest = <unsigned char*>malloc(dig_buff_len * sizeof(unsigned char))
  *     ossl.EVP_DigestInit_ex(ctx, algo, NULL)
  *     ossl.EVP_DigestUpdate(ctx, data, data_size)             # <<<<<<<<<<<<<<
@@ -6517,7 +6739,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
 */
   (void)(EVP_DigestUpdate(__pyx_v_ctx, __pyx_v_data, __pyx_v_data_size));
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":267
+  /* "dopt_pollublock_blockchain/blockchain.pyx":278
  *     ossl.EVP_DigestInit_ex(ctx, algo, NULL)
  *     ossl.EVP_DigestUpdate(ctx, data, data_size)
  *     ossl.EVP_DigestFinal_ex(ctx, digest, &digest_len)             # <<<<<<<<<<<<<<
@@ -6526,7 +6748,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
 */
   (void)(EVP_DigestFinal_ex(__pyx_v_ctx, __pyx_v_digest, (&__pyx_v_digest_len)));
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":269
+  /* "dopt_pollublock_blockchain/blockchain.pyx":280
  *     ossl.EVP_DigestFinal_ex(ctx, digest, &digest_len)
  * 
  *     ossl.EVP_MD_CTX_free(ctx)             # <<<<<<<<<<<<<<
@@ -6535,7 +6757,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
 */
   EVP_MD_CTX_free(__pyx_v_ctx);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":271
+  /* "dopt_pollublock_blockchain/blockchain.pyx":282
  *     ossl.EVP_MD_CTX_free(ctx)
  * 
  *     return digest             # <<<<<<<<<<<<<<
@@ -6545,7 +6767,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
   __pyx_r = __pyx_v_digest;
   goto __pyx_L0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":249
+  /* "dopt_pollublock_blockchain/blockchain.pyx":260
  *     return buf
  * 
  * cdef unsigned char* SHA256_digest(const void *data, size_t data_size, size_t *digest_size) nogil:             # <<<<<<<<<<<<<<
@@ -6558,7 +6780,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_d
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":274
+/* "dopt_pollublock_blockchain/blockchain.pyx":285
  * 
  * 
  * cdef unsigned char* perform_hash_c(Block *block, size_t *digest_size) nogil:             # <<<<<<<<<<<<<<
@@ -6578,17 +6800,17 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_perform_
   int __pyx_clineno = 0;
   PyGILState_STATE __pyx_gilstate_save;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":280
+  /* "dopt_pollublock_blockchain/blockchain.pyx":291
  *         unsigned char *digest
  * 
  *     serialize_res = bytes_serialize_c(block, &serialize_size)             # <<<<<<<<<<<<<<
  *     if serialize_res is NULL:
  *         return NULL
 */
-  __pyx_t_1 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_bytes_serialize_c(__pyx_v_block, (&__pyx_v_serialize_size)); if (unlikely(__pyx_t_1 == ((void *)NULL) && __Pyx_ErrOccurredWithGIL())) __PYX_ERR(0, 280, __pyx_L1_error)
+  __pyx_t_1 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_bytes_serialize_c(__pyx_v_block, (&__pyx_v_serialize_size)); if (unlikely(__pyx_t_1 == ((void *)NULL) && __Pyx_ErrOccurredWithGIL())) __PYX_ERR(0, 291, __pyx_L1_error)
   __pyx_v_serialize_res = __pyx_t_1;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":281
+  /* "dopt_pollublock_blockchain/blockchain.pyx":292
  * 
  *     serialize_res = bytes_serialize_c(block, &serialize_size)
  *     if serialize_res is NULL:             # <<<<<<<<<<<<<<
@@ -6598,7 +6820,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_perform_
   __pyx_t_2 = (__pyx_v_serialize_res == NULL);
   if (__pyx_t_2) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":282
+    /* "dopt_pollublock_blockchain/blockchain.pyx":293
  *     serialize_res = bytes_serialize_c(block, &serialize_size)
  *     if serialize_res is NULL:
  *         return NULL             # <<<<<<<<<<<<<<
@@ -6608,7 +6830,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_perform_
     __pyx_r = NULL;
     goto __pyx_L0;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":281
+    /* "dopt_pollublock_blockchain/blockchain.pyx":292
  * 
  *     serialize_res = bytes_serialize_c(block, &serialize_size)
  *     if serialize_res is NULL:             # <<<<<<<<<<<<<<
@@ -6617,17 +6839,17 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_perform_
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":283
+  /* "dopt_pollublock_blockchain/blockchain.pyx":294
  *     if serialize_res is NULL:
  *         return NULL
  *     digest = SHA256_digest(serialize_res, serialize_size, digest_size)             # <<<<<<<<<<<<<<
  *     free(serialize_res)
  *     if digest is NULL:
 */
-  __pyx_t_1 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_digest(__pyx_v_serialize_res, __pyx_v_serialize_size, __pyx_v_digest_size); if (unlikely(__pyx_t_1 == ((void *)NULL) && __Pyx_ErrOccurredWithGIL())) __PYX_ERR(0, 283, __pyx_L1_error)
+  __pyx_t_1 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_digest(__pyx_v_serialize_res, __pyx_v_serialize_size, __pyx_v_digest_size); if (unlikely(__pyx_t_1 == ((void *)NULL) && __Pyx_ErrOccurredWithGIL())) __PYX_ERR(0, 294, __pyx_L1_error)
   __pyx_v_digest = __pyx_t_1;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":284
+  /* "dopt_pollublock_blockchain/blockchain.pyx":295
  *         return NULL
  *     digest = SHA256_digest(serialize_res, serialize_size, digest_size)
  *     free(serialize_res)             # <<<<<<<<<<<<<<
@@ -6636,7 +6858,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_perform_
 */
   free(__pyx_v_serialize_res);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":285
+  /* "dopt_pollublock_blockchain/blockchain.pyx":296
  *     digest = SHA256_digest(serialize_res, serialize_size, digest_size)
  *     free(serialize_res)
  *     if digest is NULL:             # <<<<<<<<<<<<<<
@@ -6646,7 +6868,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_perform_
   __pyx_t_2 = (__pyx_v_digest == NULL);
   if (__pyx_t_2) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":286
+    /* "dopt_pollublock_blockchain/blockchain.pyx":297
  *     free(serialize_res)
  *     if digest is NULL:
  *         return NULL             # <<<<<<<<<<<<<<
@@ -6656,7 +6878,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_perform_
     __pyx_r = NULL;
     goto __pyx_L0;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":285
+    /* "dopt_pollublock_blockchain/blockchain.pyx":296
  *     digest = SHA256_digest(serialize_res, serialize_size, digest_size)
  *     free(serialize_res)
  *     if digest is NULL:             # <<<<<<<<<<<<<<
@@ -6665,7 +6887,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_perform_
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":288
+  /* "dopt_pollublock_blockchain/blockchain.pyx":299
  *         return NULL
  * 
  *     return digest             # <<<<<<<<<<<<<<
@@ -6675,7 +6897,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_perform_
   __pyx_r = __pyx_v_digest;
   goto __pyx_L0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":274
+  /* "dopt_pollublock_blockchain/blockchain.pyx":285
  * 
  * 
  * cdef unsigned char* perform_hash_c(Block *block, size_t *digest_size) nogil:             # <<<<<<<<<<<<<<
@@ -6693,7 +6915,7 @@ static unsigned char *__pyx_f_26dopt_pollublock_blockchain_10blockchain_perform_
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":291
+/* "dopt_pollublock_blockchain/blockchain.pyx":302
  * 
  * 
  * cdef int mine_block(Block *block, unsigned int difficulty, uint64_t *nonce_solution, unsigned int max_nonce=0xFFFFFFFF) nogil:             # <<<<<<<<<<<<<<
@@ -6726,7 +6948,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
     }
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":297
+  /* "dopt_pollublock_blockchain/blockchain.pyx":308
  *         unsigned char *digest
  *         size_t digest_size
  *         bint nonce_found = False             # <<<<<<<<<<<<<<
@@ -6735,17 +6957,17 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
 */
   __pyx_v_nonce_found = 0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":300
+  /* "dopt_pollublock_blockchain/blockchain.pyx":311
  *         int nonce
  * 
  *     serial_buf = bytes_serialize_c(block, &serialize_size)             # <<<<<<<<<<<<<<
  * 
  *     with nogil:
 */
-  __pyx_t_1 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_bytes_serialize_c(__pyx_v_block, (&__pyx_v_serialize_size)); if (unlikely(__pyx_t_1 == ((void *)NULL) && __Pyx_ErrOccurredWithGIL())) __PYX_ERR(0, 300, __pyx_L1_error)
+  __pyx_t_1 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_bytes_serialize_c(__pyx_v_block, (&__pyx_v_serialize_size)); if (unlikely(__pyx_t_1 == ((void *)NULL) && __Pyx_ErrOccurredWithGIL())) __PYX_ERR(0, 311, __pyx_L1_error)
   __pyx_v_serial_buf = __pyx_t_1;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":302
+  /* "dopt_pollublock_blockchain/blockchain.pyx":313
  *     serial_buf = bytes_serialize_c(block, &serialize_size)
  * 
  *     with nogil:             # <<<<<<<<<<<<<<
@@ -6758,7 +6980,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
       __Pyx_FastGIL_Remember();
       /*try:*/ {
 
-        /* "dopt_pollublock_blockchain/blockchain.pyx":303
+        /* "dopt_pollublock_blockchain/blockchain.pyx":314
  * 
  *     with nogil:
  *         for nonce in range(max_nonce):             # <<<<<<<<<<<<<<
@@ -6770,36 +6992,36 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
         for (__pyx_t_4 = 0; __pyx_t_4 < __pyx_t_3; __pyx_t_4+=1) {
           __pyx_v_nonce = __pyx_t_4;
 
-          /* "dopt_pollublock_blockchain/blockchain.pyx":304
+          /* "dopt_pollublock_blockchain/blockchain.pyx":315
  *     with nogil:
  *         for nonce in range(max_nonce):
  *             serialize_uint64(serial_buf + NONCE_OFFSET, <uint64_t>nonce)             # <<<<<<<<<<<<<<
  *             digest = SHA256_digest(serial_buf, serialize_size, &digest_size)
  * 
 */
-          __pyx_t_5 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64((__pyx_v_serial_buf + __pyx_v_26dopt_pollublock_blockchain_10blockchain_NONCE_OFFSET), ((uint64_t)__pyx_v_nonce)); if (unlikely(__pyx_t_5 == ((int)-1))) __PYX_ERR(0, 304, __pyx_L4_error)
+          __pyx_t_5 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_serialize_uint64((__pyx_v_serial_buf + __pyx_v_26dopt_pollublock_blockchain_10blockchain_NONCE_OFFSET), ((uint64_t)__pyx_v_nonce)); if (unlikely(__pyx_t_5 == ((int)-1))) __PYX_ERR(0, 315, __pyx_L4_error)
 
-          /* "dopt_pollublock_blockchain/blockchain.pyx":305
+          /* "dopt_pollublock_blockchain/blockchain.pyx":316
  *         for nonce in range(max_nonce):
  *             serialize_uint64(serial_buf + NONCE_OFFSET, <uint64_t>nonce)
  *             digest = SHA256_digest(serial_buf, serialize_size, &digest_size)             # <<<<<<<<<<<<<<
  * 
  *             if has_leading_zero_bits(digest, difficulty):
 */
-          __pyx_t_1 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_digest(__pyx_v_serial_buf, __pyx_v_serialize_size, (&__pyx_v_digest_size)); if (unlikely(__pyx_t_1 == ((void *)NULL) && __Pyx_ErrOccurredWithGIL())) __PYX_ERR(0, 305, __pyx_L4_error)
+          __pyx_t_1 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_digest(__pyx_v_serial_buf, __pyx_v_serialize_size, (&__pyx_v_digest_size)); if (unlikely(__pyx_t_1 == ((void *)NULL) && __Pyx_ErrOccurredWithGIL())) __PYX_ERR(0, 316, __pyx_L4_error)
           __pyx_v_digest = __pyx_t_1;
 
-          /* "dopt_pollublock_blockchain/blockchain.pyx":307
+          /* "dopt_pollublock_blockchain/blockchain.pyx":318
  *             digest = SHA256_digest(serial_buf, serialize_size, &digest_size)
  * 
  *             if has_leading_zero_bits(digest, difficulty):             # <<<<<<<<<<<<<<
  *                 nonce_found = True
  *                 nonce_solution[0] = nonce
 */
-          __pyx_t_6 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_leading_zero_bits(__pyx_v_digest, __pyx_v_difficulty); if (unlikely(__pyx_t_6 == ((int)-1) && __Pyx_ErrOccurredWithGIL())) __PYX_ERR(0, 307, __pyx_L4_error)
+          __pyx_t_6 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_has_leading_zero_bits(__pyx_v_digest, __pyx_v_difficulty); if (unlikely(__pyx_t_6 == ((int)-1) && __Pyx_ErrOccurredWithGIL())) __PYX_ERR(0, 318, __pyx_L4_error)
           if (__pyx_t_6) {
 
-            /* "dopt_pollublock_blockchain/blockchain.pyx":308
+            /* "dopt_pollublock_blockchain/blockchain.pyx":319
  * 
  *             if has_leading_zero_bits(digest, difficulty):
  *                 nonce_found = True             # <<<<<<<<<<<<<<
@@ -6808,7 +7030,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
 */
             __pyx_v_nonce_found = 1;
 
-            /* "dopt_pollublock_blockchain/blockchain.pyx":309
+            /* "dopt_pollublock_blockchain/blockchain.pyx":320
  *             if has_leading_zero_bits(digest, difficulty):
  *                 nonce_found = True
  *                 nonce_solution[0] = nonce             # <<<<<<<<<<<<<<
@@ -6817,7 +7039,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
 */
             (__pyx_v_nonce_solution[0]) = __pyx_v_nonce;
 
-            /* "dopt_pollublock_blockchain/blockchain.pyx":310
+            /* "dopt_pollublock_blockchain/blockchain.pyx":321
  *                 nonce_found = True
  *                 nonce_solution[0] = nonce
  *                 break             # <<<<<<<<<<<<<<
@@ -6826,7 +7048,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
 */
             goto __pyx_L7_break;
 
-            /* "dopt_pollublock_blockchain/blockchain.pyx":307
+            /* "dopt_pollublock_blockchain/blockchain.pyx":318
  *             digest = SHA256_digest(serial_buf, serialize_size, &digest_size)
  * 
  *             if has_leading_zero_bits(digest, difficulty):             # <<<<<<<<<<<<<<
@@ -6835,7 +7057,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
 */
           }
 
-          /* "dopt_pollublock_blockchain/blockchain.pyx":312
+          /* "dopt_pollublock_blockchain/blockchain.pyx":323
  *                 break
  * 
  *             free(digest)             # <<<<<<<<<<<<<<
@@ -6847,7 +7069,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
         __pyx_L7_break:;
       }
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":302
+      /* "dopt_pollublock_blockchain/blockchain.pyx":313
  *     serial_buf = bytes_serialize_c(block, &serialize_size)
  * 
  *     with nogil:             # <<<<<<<<<<<<<<
@@ -6869,7 +7091,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
       }
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":314
+  /* "dopt_pollublock_blockchain/blockchain.pyx":325
  *             free(digest)
  * 
  *     free(serial_buf)             # <<<<<<<<<<<<<<
@@ -6878,7 +7100,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
 */
   free(__pyx_v_serial_buf);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":316
+  /* "dopt_pollublock_blockchain/blockchain.pyx":327
  *     free(serial_buf)
  * 
  *     if not nonce_found:             # <<<<<<<<<<<<<<
@@ -6888,7 +7110,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
   __pyx_t_6 = (!__pyx_v_nonce_found);
   if (__pyx_t_6) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":317
+    /* "dopt_pollublock_blockchain/blockchain.pyx":328
  * 
  *     if not nonce_found:
  *         return 1             # <<<<<<<<<<<<<<
@@ -6898,7 +7120,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
     __pyx_r = 1;
     goto __pyx_L0;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":316
+    /* "dopt_pollublock_blockchain/blockchain.pyx":327
  *     free(serial_buf)
  * 
  *     if not nonce_found:             # <<<<<<<<<<<<<<
@@ -6907,7 +7129,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":319
+  /* "dopt_pollublock_blockchain/blockchain.pyx":330
  *         return 1
  * 
  *     return 0             # <<<<<<<<<<<<<<
@@ -6917,7 +7139,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
   __pyx_r = 0;
   goto __pyx_L0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":291
+  /* "dopt_pollublock_blockchain/blockchain.pyx":302
  * 
  * 
  * cdef int mine_block(Block *block, unsigned int difficulty, uint64_t *nonce_solution, unsigned int max_nonce=0xFFFFFFFF) nogil:             # <<<<<<<<<<<<<<
@@ -6935,7 +7157,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(::Block
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":333
+/* "dopt_pollublock_blockchain/blockchain.pyx":344
  *         readonly object _engine
  * 
  *     def __cinit__(self, *args, **kwargs):             # <<<<<<<<<<<<<<
@@ -6989,7 +7211,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain___cin
   int __pyx_clineno = 0;
   __Pyx_RefNannySetupContext("__cinit__", 0);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":334
+  /* "dopt_pollublock_blockchain/blockchain.pyx":345
  * 
  *     def __cinit__(self, *args, **kwargs):
  *         self._difficulty = 26             # <<<<<<<<<<<<<<
@@ -6998,7 +7220,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain___cin
 */
   __pyx_v_self->_difficulty = 26;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":335
+  /* "dopt_pollublock_blockchain/blockchain.pyx":346
  *     def __cinit__(self, *args, **kwargs):
  *         self._difficulty = 26
  *         self._index = <uint64_t>0             # <<<<<<<<<<<<<<
@@ -7007,7 +7229,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain___cin
 */
   __pyx_v_self->_index = ((uint64_t)0);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":336
+  /* "dopt_pollublock_blockchain/blockchain.pyx":347
  *         self._difficulty = 26
  *         self._index = <uint64_t>0
  *         self._genesis_done = False             # <<<<<<<<<<<<<<
@@ -7016,7 +7238,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain___cin
 */
   __pyx_v_self->_genesis_done = 0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":337
+  /* "dopt_pollublock_blockchain/blockchain.pyx":348
  *         self._index = <uint64_t>0
  *         self._genesis_done = False
  *         self._loaded = False             # <<<<<<<<<<<<<<
@@ -7025,7 +7247,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain___cin
 */
   __pyx_v_self->_loaded = 0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":338
+  /* "dopt_pollublock_blockchain/blockchain.pyx":349
  *         self._genesis_done = False
  *         self._loaded = False
  *         self._chain_map = new unordered_map[uint64_t, Block*]()             # <<<<<<<<<<<<<<
@@ -7036,11 +7258,11 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain___cin
     __pyx_t_1 = new std::unordered_map<uint64_t,::Block *> ();
   } catch(...) {
     __Pyx_CppExn2PyErr();
-    __PYX_ERR(0, 338, __pyx_L1_error)
+    __PYX_ERR(0, 349, __pyx_L1_error)
   }
   __pyx_v_self->_chain_map = __pyx_t_1;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":339
+  /* "dopt_pollublock_blockchain/blockchain.pyx":350
  *         self._loaded = False
  *         self._chain_map = new unordered_map[uint64_t, Block*]()
  *         self._chain = new vector[Block*]()             # <<<<<<<<<<<<<<
@@ -7051,11 +7273,11 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain___cin
     __pyx_t_2 = new std::vector<::Block *> ();
   } catch(...) {
     __Pyx_CppExn2PyErr();
-    __PYX_ERR(0, 339, __pyx_L1_error)
+    __PYX_ERR(0, 350, __pyx_L1_error)
   }
   __pyx_v_self->_chain = __pyx_t_2;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":340
+  /* "dopt_pollublock_blockchain/blockchain.pyx":351
  *         self._chain_map = new unordered_map[uint64_t, Block*]()
  *         self._chain = new vector[Block*]()
  *         if self._chain_map is NULL:             # <<<<<<<<<<<<<<
@@ -7065,7 +7287,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain___cin
   __pyx_t_3 = (__pyx_v_self->_chain_map == NULL);
   if (unlikely(__pyx_t_3)) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":341
+    /* "dopt_pollublock_blockchain/blockchain.pyx":352
  *         self._chain = new vector[Block*]()
  *         if self._chain_map is NULL:
  *             raise MemoryError("Could not allocate hasmap")             # <<<<<<<<<<<<<<
@@ -7078,14 +7300,14 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain___cin
       PyObject *__pyx_callargs[2] = {__pyx_t_5, __pyx_mstate_global->__pyx_kp_u_Could_not_allocate_hasmap};
       __pyx_t_4 = __Pyx_PyObject_FastCall((PyObject*)(((PyTypeObject*)PyExc_MemoryError)), __pyx_callargs+__pyx_t_6, (2-__pyx_t_6) | (__pyx_t_6*__Pyx_PY_VECTORCALL_ARGUMENTS_OFFSET));
       __Pyx_XDECREF(__pyx_t_5); __pyx_t_5 = 0;
-      if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 341, __pyx_L1_error)
+      if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 352, __pyx_L1_error)
       __Pyx_GOTREF(__pyx_t_4);
     }
     __Pyx_Raise(__pyx_t_4, 0, 0, 0);
     __Pyx_DECREF(__pyx_t_4); __pyx_t_4 = 0;
-    __PYX_ERR(0, 341, __pyx_L1_error)
+    __PYX_ERR(0, 352, __pyx_L1_error)
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":340
+    /* "dopt_pollublock_blockchain/blockchain.pyx":351
  *         self._chain_map = new unordered_map[uint64_t, Block*]()
  *         self._chain = new vector[Block*]()
  *         if self._chain_map is NULL:             # <<<<<<<<<<<<<<
@@ -7094,7 +7316,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain___cin
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":342
+  /* "dopt_pollublock_blockchain/blockchain.pyx":353
  *         if self._chain_map is NULL:
  *             raise MemoryError("Could not allocate hasmap")
  *         if self._chain is NULL:             # <<<<<<<<<<<<<<
@@ -7104,7 +7326,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain___cin
   __pyx_t_3 = (__pyx_v_self->_chain == NULL);
   if (unlikely(__pyx_t_3)) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":343
+    /* "dopt_pollublock_blockchain/blockchain.pyx":354
  *             raise MemoryError("Could not allocate hasmap")
  *         if self._chain is NULL:
  *             raise MemoryError("Could not allocate vector")             # <<<<<<<<<<<<<<
@@ -7117,14 +7339,14 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain___cin
       PyObject *__pyx_callargs[2] = {__pyx_t_5, __pyx_mstate_global->__pyx_kp_u_Could_not_allocate_vector};
       __pyx_t_4 = __Pyx_PyObject_FastCall((PyObject*)(((PyTypeObject*)PyExc_MemoryError)), __pyx_callargs+__pyx_t_6, (2-__pyx_t_6) | (__pyx_t_6*__Pyx_PY_VECTORCALL_ARGUMENTS_OFFSET));
       __Pyx_XDECREF(__pyx_t_5); __pyx_t_5 = 0;
-      if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 343, __pyx_L1_error)
+      if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 354, __pyx_L1_error)
       __Pyx_GOTREF(__pyx_t_4);
     }
     __Pyx_Raise(__pyx_t_4, 0, 0, 0);
     __Pyx_DECREF(__pyx_t_4); __pyx_t_4 = 0;
-    __PYX_ERR(0, 343, __pyx_L1_error)
+    __PYX_ERR(0, 354, __pyx_L1_error)
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":342
+    /* "dopt_pollublock_blockchain/blockchain.pyx":353
  *         if self._chain_map is NULL:
  *             raise MemoryError("Could not allocate hasmap")
  *         if self._chain is NULL:             # <<<<<<<<<<<<<<
@@ -7133,7 +7355,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain___cin
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":333
+  /* "dopt_pollublock_blockchain/blockchain.pyx":344
  *         readonly object _engine
  * 
  *     def __cinit__(self, *args, **kwargs):             # <<<<<<<<<<<<<<
@@ -7154,7 +7376,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain___cin
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":345
+/* "dopt_pollublock_blockchain/blockchain.pyx":356
  *             raise MemoryError("Could not allocate vector")
  * 
  *     def __init__(self, db_path):             # <<<<<<<<<<<<<<
@@ -7184,32 +7406,32 @@ static int __pyx_pw_26dopt_pollublock_blockchain_10blockchain_10Blockchain_3__in
   {
     PyObject ** const __pyx_pyargnames[] = {&__pyx_mstate_global->__pyx_n_u_db_path,0};
     const Py_ssize_t __pyx_kwds_len = (__pyx_kwds) ? __Pyx_NumKwargs_VARARGS(__pyx_kwds) : 0;
-    if (unlikely(__pyx_kwds_len) < 0) __PYX_ERR(0, 345, __pyx_L3_error)
+    if (unlikely(__pyx_kwds_len) < 0) __PYX_ERR(0, 356, __pyx_L3_error)
     if (__pyx_kwds_len > 0) {
       switch (__pyx_nargs) {
         case  1:
         values[0] = __Pyx_ArgRef_VARARGS(__pyx_args, 0);
-        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[0])) __PYX_ERR(0, 345, __pyx_L3_error)
+        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[0])) __PYX_ERR(0, 356, __pyx_L3_error)
         CYTHON_FALLTHROUGH;
         case  0: break;
         default: goto __pyx_L5_argtuple_error;
       }
       const Py_ssize_t kwd_pos_args = __pyx_nargs;
-      if (__Pyx_ParseKeywords(__pyx_kwds, __pyx_kwvalues, __pyx_pyargnames, 0, values, kwd_pos_args, __pyx_kwds_len, "__init__", 0) < (0)) __PYX_ERR(0, 345, __pyx_L3_error)
+      if (__Pyx_ParseKeywords(__pyx_kwds, __pyx_kwvalues, __pyx_pyargnames, 0, values, kwd_pos_args, __pyx_kwds_len, "__init__", 0) < (0)) __PYX_ERR(0, 356, __pyx_L3_error)
       for (Py_ssize_t i = __pyx_nargs; i < 1; i++) {
-        if (unlikely(!values[i])) { __Pyx_RaiseArgtupleInvalid("__init__", 1, 1, 1, i); __PYX_ERR(0, 345, __pyx_L3_error) }
+        if (unlikely(!values[i])) { __Pyx_RaiseArgtupleInvalid("__init__", 1, 1, 1, i); __PYX_ERR(0, 356, __pyx_L3_error) }
       }
     } else if (unlikely(__pyx_nargs != 1)) {
       goto __pyx_L5_argtuple_error;
     } else {
       values[0] = __Pyx_ArgRef_VARARGS(__pyx_args, 0);
-      if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[0])) __PYX_ERR(0, 345, __pyx_L3_error)
+      if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[0])) __PYX_ERR(0, 356, __pyx_L3_error)
     }
     __pyx_v_db_path = values[0];
   }
   goto __pyx_L6_skip;
   __pyx_L5_argtuple_error:;
-  __Pyx_RaiseArgtupleInvalid("__init__", 1, 1, 1, __pyx_nargs); __PYX_ERR(0, 345, __pyx_L3_error)
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@@ -7246,7 +7468,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_2__in
   int __pyx_clineno = 0;
   __Pyx_RefNannySetupContext("__init__", 0);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":346
+  /* "dopt_pollublock_blockchain/blockchain.pyx":357
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  *     def __init__(self, db_path):
  *         self.db_path = Path(db_path).resolve()             # <<<<<<<<<<<<<<
@@ -7254,7 +7476,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_2__in
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-    if (unlikely(!__pyx_t_3)) __PYX_ERR(0, 346, __pyx_L1_error)
+    if (unlikely(!__pyx_t_3)) __PYX_ERR(0, 357, __pyx_L1_error)
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@@ -7284,7 +7506,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_2__in
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@@ -7293,14 +7515,14 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_2__in
   __pyx_v_self->db_path = __pyx_t_1;
   __pyx_t_1 = 0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":347
+  /* "dopt_pollublock_blockchain/blockchain.pyx":358
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-  __pyx_t_2 = __Pyx_PyObject_GetAttrStr(__pyx_v_self->db_path, __pyx_mstate_global->__pyx_n_u_parent); if (unlikely(!__pyx_t_2)) __PYX_ERR(0, 347, __pyx_L1_error)
+  __pyx_t_2 = __Pyx_PyObject_GetAttrStr(__pyx_v_self->db_path, __pyx_mstate_global->__pyx_n_u_parent); if (unlikely(!__pyx_t_2)) __PYX_ERR(0, 358, __pyx_L1_error)
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@@ -7310,15 +7532,15 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_2__in
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-  __pyx_t_7 = __Pyx_PyObject_IsTrue(__pyx_t_1); if (unlikely((__pyx_t_7 < 0))) __PYX_ERR(0, 347, __pyx_L1_error)
+  __pyx_t_7 = __Pyx_PyObject_IsTrue(__pyx_t_1); if (unlikely((__pyx_t_7 < 0))) __PYX_ERR(0, 358, __pyx_L1_error)
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":348
+    /* "dopt_pollublock_blockchain/blockchain.pyx":359
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  *         if not self.db_path.parent.exists():
  *             raise FileNotFoundError(             # <<<<<<<<<<<<<<
@@ -7331,14 +7553,14 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_2__in
       PyObject *__pyx_callargs[2] = {__pyx_t_2, __pyx_mstate_global->__pyx_kp_u_The_parent_directory_of_the_prov};
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-      if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 348, __pyx_L1_error)
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     __Pyx_DECREF(__pyx_t_1); __pyx_t_1 = 0;
-    __PYX_ERR(0, 348, __pyx_L1_error)
+    __PYX_ERR(0, 359, __pyx_L1_error)
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":347
+    /* "dopt_pollublock_blockchain/blockchain.pyx":358
  *     def __init__(self, db_path):
  *         self.db_path = Path(db_path).resolve()
  *         if not self.db_path.parent.exists():             # <<<<<<<<<<<<<<
@@ -7347,7 +7569,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_2__in
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":352
+  /* "dopt_pollublock_blockchain/blockchain.pyx":363
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  *         self._engine = sql.create_engine(f"sqlite:///{str(self.db_path)}")             # <<<<<<<<<<<<<<
@@ -7355,14 +7577,14 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_2__in
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 */
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+  __Pyx_GetModuleGlobalName(__pyx_t_3, __pyx_mstate_global->__pyx_n_u_sql); if (unlikely(!__pyx_t_3)) __PYX_ERR(0, 363, __pyx_L1_error)
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-  __pyx_t_5 = __Pyx_PyObject_GetAttrStr(__pyx_t_3, __pyx_mstate_global->__pyx_n_u_create_engine); if (unlikely(!__pyx_t_5)) __PYX_ERR(0, 352, __pyx_L1_error)
+  __pyx_t_5 = __Pyx_PyObject_GetAttrStr(__pyx_t_3, __pyx_mstate_global->__pyx_n_u_create_engine); if (unlikely(!__pyx_t_5)) __PYX_ERR(0, 363, __pyx_L1_error)
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-  __pyx_t_3 = __Pyx_PyObject_Unicode(__pyx_v_self->db_path); if (unlikely(!__pyx_t_3)) __PYX_ERR(0, 352, __pyx_L1_error)
+  __pyx_t_3 = __Pyx_PyObject_Unicode(__pyx_v_self->db_path); if (unlikely(!__pyx_t_3)) __PYX_ERR(0, 363, __pyx_L1_error)
   __Pyx_GOTREF(__pyx_t_3);
-  __pyx_t_4 = __Pyx_PyUnicode_Concat(__pyx_mstate_global->__pyx_kp_u_sqlite, __pyx_t_3); if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 352, __pyx_L1_error)
+  __pyx_t_4 = __Pyx_PyUnicode_Concat(__pyx_mstate_global->__pyx_kp_u_sqlite, __pyx_t_3); if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 363, __pyx_L1_error)
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   __Pyx_DECREF(__pyx_t_3); __pyx_t_3 = 0;
   __pyx_t_6 = 1;
@@ -7383,7 +7605,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_2__in
     __Pyx_XDECREF(__pyx_t_2); __pyx_t_2 = 0;
     __Pyx_DECREF(__pyx_t_4); __pyx_t_4 = 0;
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-    if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 352, __pyx_L1_error)
+    if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 363, __pyx_L1_error)
     __Pyx_GOTREF(__pyx_t_1);
   }
   __Pyx_GIVEREF(__pyx_t_1);
@@ -7392,16 +7614,16 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_2__in
   __pyx_v_self->_engine = __pyx_t_1;
   __pyx_t_1 = 0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":353
+  /* "dopt_pollublock_blockchain/blockchain.pyx":364
  * 
  *         self._engine = sql.create_engine(f"sqlite:///{str(self.db_path)}")
  *         db.metadata_blockchain.create_all(self._engine)             # <<<<<<<<<<<<<<
  * 
  *     def __dealloc__(self):
 */
-  __Pyx_GetModuleGlobalName(__pyx_t_4, __pyx_mstate_global->__pyx_n_u_db); if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 353, __pyx_L1_error)
+  __Pyx_GetModuleGlobalName(__pyx_t_4, __pyx_mstate_global->__pyx_n_u_db); if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 364, __pyx_L1_error)
   __Pyx_GOTREF(__pyx_t_4);
-  __pyx_t_2 = __Pyx_PyObject_GetAttrStr(__pyx_t_4, __pyx_mstate_global->__pyx_n_u_metadata_blockchain); if (unlikely(!__pyx_t_2)) __PYX_ERR(0, 353, __pyx_L1_error)
+  __pyx_t_2 = __Pyx_PyObject_GetAttrStr(__pyx_t_4, __pyx_mstate_global->__pyx_n_u_metadata_blockchain); if (unlikely(!__pyx_t_2)) __PYX_ERR(0, 364, __pyx_L1_error)
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@@ -7412,12 +7634,12 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_2__in
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     __Pyx_XDECREF(__pyx_t_5); __pyx_t_5 = 0;
     __Pyx_DECREF(__pyx_t_2); __pyx_t_2 = 0;
-    if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 353, __pyx_L1_error)
+    if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 364, __pyx_L1_error)
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   }
   __Pyx_DECREF(__pyx_t_1); __pyx_t_1 = 0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":345
+  /* "dopt_pollublock_blockchain/blockchain.pyx":356
  *             raise MemoryError("Could not allocate vector")
  * 
  *     def __init__(self, db_path):             # <<<<<<<<<<<<<<
@@ -7441,7 +7663,7 @@ static int __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_2__in
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":355
+/* "dopt_pollublock_blockchain/blockchain.pyx":366
  *         db.metadata_blockchain.create_all(self._engine)
  * 
  *     def __dealloc__(self):             # <<<<<<<<<<<<<<
@@ -7466,7 +7688,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_4__d
   std::unordered_map<uint64_t,::Block *> ::iterator __pyx_v_it;
   int __pyx_t_1;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":357
+  /* "dopt_pollublock_blockchain/blockchain.pyx":368
  *     def __dealloc__(self):
  *         # ownership is typically not transferred from the Blockchain extension class
  *         cdef BcHashmap.iterator it = self._chain_map.begin()             # <<<<<<<<<<<<<<
@@ -7475,7 +7697,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_4__d
 */
   __pyx_v_it = __pyx_v_self->_chain_map->begin();
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":358
+  /* "dopt_pollublock_blockchain/blockchain.pyx":369
  *         # ownership is typically not transferred from the Blockchain extension class
  *         cdef BcHashmap.iterator it = self._chain_map.begin()
  *         if self._chain_map is not NULL:             # <<<<<<<<<<<<<<
@@ -7485,7 +7707,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_4__d
   __pyx_t_1 = (__pyx_v_self->_chain_map != NULL);
   if (__pyx_t_1) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":359
+    /* "dopt_pollublock_blockchain/blockchain.pyx":370
  *         cdef BcHashmap.iterator it = self._chain_map.begin()
  *         if self._chain_map is not NULL:
  *             while it != self._chain_map.end():             # <<<<<<<<<<<<<<
@@ -7496,7 +7718,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_4__d
       __pyx_t_1 = (__pyx_v_it != __pyx_v_self->_chain_map->end());
       if (!__pyx_t_1) break;
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":360
+      /* "dopt_pollublock_blockchain/blockchain.pyx":371
  *         if self._chain_map is not NULL:
  *             while it != self._chain_map.end():
  *                 del dereference(it).second             # <<<<<<<<<<<<<<
@@ -7505,7 +7727,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_4__d
 */
       delete (*__pyx_v_it).second;
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":361
+      /* "dopt_pollublock_blockchain/blockchain.pyx":372
  *             while it != self._chain_map.end():
  *                 del dereference(it).second
  *                 postincrement(it)             # <<<<<<<<<<<<<<
@@ -7515,7 +7737,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_4__d
       (void)((__pyx_v_it++));
     }
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":363
+    /* "dopt_pollublock_blockchain/blockchain.pyx":374
  *                 postincrement(it)
  * 
  *             del self._chain_map             # <<<<<<<<<<<<<<
@@ -7524,7 +7746,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_4__d
 */
     delete __pyx_v_self->_chain_map;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":364
+    /* "dopt_pollublock_blockchain/blockchain.pyx":375
  * 
  *             del self._chain_map
  *             self._chain_map = NULL             # <<<<<<<<<<<<<<
@@ -7533,7 +7755,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_4__d
 */
     __pyx_v_self->_chain_map = NULL;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":358
+    /* "dopt_pollublock_blockchain/blockchain.pyx":369
  *         # ownership is typically not transferred from the Blockchain extension class
  *         cdef BcHashmap.iterator it = self._chain_map.begin()
  *         if self._chain_map is not NULL:             # <<<<<<<<<<<<<<
@@ -7542,7 +7764,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_4__d
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":366
+  /* "dopt_pollublock_blockchain/blockchain.pyx":377
  *             self._chain_map = NULL
  * 
  *         if self._chain is not NULL:             # <<<<<<<<<<<<<<
@@ -7552,7 +7774,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_4__d
   __pyx_t_1 = (__pyx_v_self->_chain != NULL);
   if (__pyx_t_1) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":367
+    /* "dopt_pollublock_blockchain/blockchain.pyx":378
  * 
  *         if self._chain is not NULL:
  *             del self._chain             # <<<<<<<<<<<<<<
@@ -7561,7 +7783,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_4__d
 */
     delete __pyx_v_self->_chain;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":368
+    /* "dopt_pollublock_blockchain/blockchain.pyx":379
  *         if self._chain is not NULL:
  *             del self._chain
  *             self._chain = NULL             # <<<<<<<<<<<<<<
@@ -7570,7 +7792,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_4__d
 */
     __pyx_v_self->_chain = NULL;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":366
+    /* "dopt_pollublock_blockchain/blockchain.pyx":377
  *             self._chain_map = NULL
  * 
  *         if self._chain is not NULL:             # <<<<<<<<<<<<<<
@@ -7579,7 +7801,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_4__d
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":355
+  /* "dopt_pollublock_blockchain/blockchain.pyx":366
  *         db.metadata_blockchain.create_all(self._engine)
  * 
  *     def __dealloc__(self):             # <<<<<<<<<<<<<<
@@ -7590,7 +7812,7 @@ static void __pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain_4__d
   /* function exit code */
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":370
+/* "dopt_pollublock_blockchain/blockchain.pyx":381
  *             self._chain = NULL
  * 
  *     cdef Block* get_block_c(self, uint64_t idx) nogil:             # <<<<<<<<<<<<<<
@@ -7602,7 +7824,7 @@ static ::Block *__pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_g
   ::Block *__pyx_r;
   int __pyx_t_1;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":371
+  /* "dopt_pollublock_blockchain/blockchain.pyx":382
  * 
  *     cdef Block* get_block_c(self, uint64_t idx) nogil:
  *         if idx > self._index:             # <<<<<<<<<<<<<<
@@ -7612,7 +7834,7 @@ static ::Block *__pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_g
   __pyx_t_1 = (__pyx_v_idx > __pyx_v_self->_index);
   if (__pyx_t_1) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":372
+    /* "dopt_pollublock_blockchain/blockchain.pyx":383
  *     cdef Block* get_block_c(self, uint64_t idx) nogil:
  *         if idx > self._index:
  *             return NULL             # <<<<<<<<<<<<<<
@@ -7622,7 +7844,7 @@ static ::Block *__pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_g
     __pyx_r = NULL;
     goto __pyx_L0;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":371
+    /* "dopt_pollublock_blockchain/blockchain.pyx":382
  * 
  *     cdef Block* get_block_c(self, uint64_t idx) nogil:
  *         if idx > self._index:             # <<<<<<<<<<<<<<
@@ -7631,7 +7853,7 @@ static ::Block *__pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_g
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":373
+  /* "dopt_pollublock_blockchain/blockchain.pyx":384
  *         if idx > self._index:
  *             return NULL
  *         return self._chain_map[0][idx]             # <<<<<<<<<<<<<<
@@ -7641,7 +7863,7 @@ static ::Block *__pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_g
   __pyx_r = ((__pyx_v_self->_chain_map[0])[__pyx_v_idx]);
   goto __pyx_L0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":370
+  /* "dopt_pollublock_blockchain/blockchain.pyx":381
  *             self._chain = NULL
  * 
  *     cdef Block* get_block_c(self, uint64_t idx) nogil:             # <<<<<<<<<<<<<<
@@ -7654,7 +7876,7 @@ static ::Block *__pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_g
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":375
+/* "dopt_pollublock_blockchain/blockchain.pyx":386
  *         return self._chain_map[0][idx]
  * 
  *     cdef void add_block_from_loading(self, Block *block) nogil:             # <<<<<<<<<<<<<<
@@ -7670,7 +7892,7 @@ static void __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_b
   int __pyx_clineno = 0;
   PyGILState_STATE __pyx_gilstate_save;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":376
+  /* "dopt_pollublock_blockchain/blockchain.pyx":387
  * 
  *     cdef void add_block_from_loading(self, Block *block) nogil:
  *         self._chain[0].push_back(block)             # <<<<<<<<<<<<<<
@@ -7683,10 +7905,10 @@ static void __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_b
     PyGILState_STATE __pyx_gilstate_save = __Pyx_PyGILState_Ensure();
     __Pyx_CppExn2PyErr();
     __Pyx_PyGILState_Release(__pyx_gilstate_save);
-    __PYX_ERR(0, 376, __pyx_L1_error)
+    __PYX_ERR(0, 387, __pyx_L1_error)
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":377
+  /* "dopt_pollublock_blockchain/blockchain.pyx":388
  *     cdef void add_block_from_loading(self, Block *block) nogil:
  *         self._chain[0].push_back(block)
  *         self._chain_map[0][block.index] = block             # <<<<<<<<<<<<<<
@@ -7695,7 +7917,7 @@ static void __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_b
 */
   ((__pyx_v_self->_chain_map[0])[__pyx_v_block->index]) = __pyx_v_block;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":378
+  /* "dopt_pollublock_blockchain/blockchain.pyx":389
  *         self._chain[0].push_back(block)
  *         self._chain_map[0][block.index] = block
  *         self._index = block.index             # <<<<<<<<<<<<<<
@@ -7705,7 +7927,7 @@ static void __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_b
   __pyx_t_1 = __pyx_v_block->index;
   __pyx_v_self->_index = __pyx_t_1;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":379
+  /* "dopt_pollublock_blockchain/blockchain.pyx":390
  *         self._chain_map[0][block.index] = block
  *         self._index = block.index
  *         if not self._genesis_done:             # <<<<<<<<<<<<<<
@@ -7715,7 +7937,7 @@ static void __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_b
   __pyx_t_2 = (!__pyx_v_self->_genesis_done);
   if (__pyx_t_2) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":380
+    /* "dopt_pollublock_blockchain/blockchain.pyx":391
  *         self._index = block.index
  *         if not self._genesis_done:
  *             self._genesis_done = True             # <<<<<<<<<<<<<<
@@ -7724,7 +7946,7 @@ static void __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_b
 */
     __pyx_v_self->_genesis_done = 1;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":379
+    /* "dopt_pollublock_blockchain/blockchain.pyx":390
  *         self._chain_map[0][block.index] = block
  *         self._index = block.index
  *         if not self._genesis_done:             # <<<<<<<<<<<<<<
@@ -7733,7 +7955,7 @@ static void __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_b
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":375
+  /* "dopt_pollublock_blockchain/blockchain.pyx":386
  *         return self._chain_map[0][idx]
  * 
  *     cdef void add_block_from_loading(self, Block *block) nogil:             # <<<<<<<<<<<<<<
@@ -7750,7 +7972,7 @@ static void __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_b
   __pyx_L0:;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":382
+/* "dopt_pollublock_blockchain/blockchain.pyx":393
  *             self._genesis_done = True
  * 
  *     cdef int add_block(self, Block *block) nogil:             # <<<<<<<<<<<<<<
@@ -7780,18 +8002,18 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
   PyGILState_STATE __pyx_gilstate_save;
   __Pyx_RefNannySetupContext("add_block", 1);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":388
+  /* "dopt_pollublock_blockchain/blockchain.pyx":399
  *             unsigned char *sha256_digest
  *         # mine block
  *         if mine_block(block, self._difficulty, &mined_nonce) != 0:             # <<<<<<<<<<<<<<
  *             return 1
  *         block.nonce = mined_nonce
 */
-  __pyx_t_1 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(__pyx_v_block, __pyx_v_self->_difficulty, (&__pyx_v_mined_nonce), NULL); if (unlikely(__pyx_t_1 == ((int)-1) && __Pyx_ErrOccurredWithGIL())) __PYX_ERR(0, 388, __pyx_L1_error)
+  __pyx_t_1 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_mine_block(__pyx_v_block, __pyx_v_self->_difficulty, (&__pyx_v_mined_nonce), NULL); if (unlikely(__pyx_t_1 == ((int)-1) && __Pyx_ErrOccurredWithGIL())) __PYX_ERR(0, 399, __pyx_L1_error)
   __pyx_t_2 = (__pyx_t_1 != 0);
   if (__pyx_t_2) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":389
+    /* "dopt_pollublock_blockchain/blockchain.pyx":400
  *         # mine block
  *         if mine_block(block, self._difficulty, &mined_nonce) != 0:
  *             return 1             # <<<<<<<<<<<<<<
@@ -7801,7 +8023,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
     __pyx_r = 1;
     goto __pyx_L0;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":388
+    /* "dopt_pollublock_blockchain/blockchain.pyx":399
  *             unsigned char *sha256_digest
  *         # mine block
  *         if mine_block(block, self._difficulty, &mined_nonce) != 0:             # <<<<<<<<<<<<<<
@@ -7810,7 +8032,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":390
+  /* "dopt_pollublock_blockchain/blockchain.pyx":401
  *         if mine_block(block, self._difficulty, &mined_nonce) != 0:
  *             return 1
  *         block.nonce = mined_nonce             # <<<<<<<<<<<<<<
@@ -7819,17 +8041,17 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
 */
   __pyx_v_block->nonce = __pyx_v_mined_nonce;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":392
+  /* "dopt_pollublock_blockchain/blockchain.pyx":403
  *         block.nonce = mined_nonce
  *         # hash block, add hash to block, add block to blockchain hashmap
  *         sha256_digest = perform_hash_c(block, &digest_size)             # <<<<<<<<<<<<<<
  *         with gil:
  *             block.hash = bytes(sha256_digest[:digest_size]).hex().encode("UTF-8")
 */
-  __pyx_t_3 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_perform_hash_c(__pyx_v_block, (&__pyx_v_digest_size)); if (unlikely(__pyx_t_3 == ((void *)NULL) && __Pyx_ErrOccurredWithGIL())) __PYX_ERR(0, 392, __pyx_L1_error)
+  __pyx_t_3 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_perform_hash_c(__pyx_v_block, (&__pyx_v_digest_size)); if (unlikely(__pyx_t_3 == ((void *)NULL) && __Pyx_ErrOccurredWithGIL())) __PYX_ERR(0, 403, __pyx_L1_error)
   __pyx_v_sha256_digest = __pyx_t_3;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":393
+  /* "dopt_pollublock_blockchain/blockchain.pyx":404
  *         # hash block, add hash to block, add block to blockchain hashmap
  *         sha256_digest = perform_hash_c(block, &digest_size)
  *         with gil:             # <<<<<<<<<<<<<<
@@ -7840,7 +8062,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
       PyGILState_STATE __pyx_gilstate_save = __Pyx_PyGILState_Ensure();
       /*try:*/ {
 
-        /* "dopt_pollublock_blockchain/blockchain.pyx":394
+        /* "dopt_pollublock_blockchain/blockchain.pyx":405
  *         sha256_digest = perform_hash_c(block, &digest_size)
  *         with gil:
  *             block.hash = bytes(sha256_digest[:digest_size]).hex().encode("UTF-8")             # <<<<<<<<<<<<<<
@@ -7848,7 +8070,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
  *         self._chain[0].push_back(block)
 */
         __pyx_t_7 = NULL;
-        __pyx_t_8 = __Pyx_PyBytes_FromStringAndSize(((char const *)__pyx_v_sha256_digest) + 0, __pyx_v_digest_size - 0); if (unlikely(!__pyx_t_8)) __PYX_ERR(0, 394, __pyx_L5_error)
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@@ -7856,7 +8078,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
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@@ -7867,18 +8089,18 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
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+        __pyx_t_10 = __pyx_convert_string_from_py_6libcpp_6string_std__in_string(__pyx_t_6); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 405, __pyx_L5_error)
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-      /* "dopt_pollublock_blockchain/blockchain.pyx":393
+      /* "dopt_pollublock_blockchain/blockchain.pyx":404
  *         # hash block, add hash to block, add block to blockchain hashmap
  *         sha256_digest = perform_hash_c(block, &digest_size)
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@@ -7898,7 +8120,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
       }
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":395
+  /* "dopt_pollublock_blockchain/blockchain.pyx":406
  *         with gil:
  *             block.hash = bytes(sha256_digest[:digest_size]).hex().encode("UTF-8")
  *         free(sha256_digest)             # <<<<<<<<<<<<<<
@@ -7907,7 +8129,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
 */
   free(__pyx_v_sha256_digest);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":396
+  /* "dopt_pollublock_blockchain/blockchain.pyx":407
  *             block.hash = bytes(sha256_digest[:digest_size]).hex().encode("UTF-8")
  *         free(sha256_digest)
  *         self._chain[0].push_back(block)             # <<<<<<<<<<<<<<
@@ -7920,10 +8142,10 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
     PyGILState_STATE __pyx_gilstate_save = __Pyx_PyGILState_Ensure();
     __Pyx_CppExn2PyErr();
     __Pyx_PyGILState_Release(__pyx_gilstate_save);
-    __PYX_ERR(0, 396, __pyx_L1_error)
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   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":397
+  /* "dopt_pollublock_blockchain/blockchain.pyx":408
  *         free(sha256_digest)
  *         self._chain[0].push_back(block)
  *         self._chain_map[0][block.index] = block             # <<<<<<<<<<<<<<
@@ -7932,7 +8154,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
 */
   ((__pyx_v_self->_chain_map[0])[__pyx_v_block->index]) = __pyx_v_block;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":399
+  /* "dopt_pollublock_blockchain/blockchain.pyx":410
  *         self._chain_map[0][block.index] = block
  * 
  *         if self._genesis_done:             # <<<<<<<<<<<<<<
@@ -7941,7 +8163,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
 */
   if (__pyx_v_self->_genesis_done) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":400
+    /* "dopt_pollublock_blockchain/blockchain.pyx":411
  * 
  *         if self._genesis_done:
  *             self._index += 1             # <<<<<<<<<<<<<<
@@ -7950,7 +8172,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
 */
     __pyx_v_self->_index = (__pyx_v_self->_index + 1);
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":399
+    /* "dopt_pollublock_blockchain/blockchain.pyx":410
  *         self._chain_map[0][block.index] = block
  * 
  *         if self._genesis_done:             # <<<<<<<<<<<<<<
@@ -7959,7 +8181,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":402
+  /* "dopt_pollublock_blockchain/blockchain.pyx":413
  *             self._index += 1
  * 
  *         return 0             # <<<<<<<<<<<<<<
@@ -7969,7 +8191,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
   __pyx_r = 0;
   goto __pyx_L0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":382
+  /* "dopt_pollublock_blockchain/blockchain.pyx":393
  *             self._genesis_done = True
  * 
  *     cdef int add_block(self, Block *block) nogil:             # <<<<<<<<<<<<<<
@@ -7993,7 +8215,7 @@ static int __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchain_add_bl
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":404
+/* "dopt_pollublock_blockchain/blockchain.pyx":415
  *         return 0
  * 
  *     cdef string hash_data(self, data):             # <<<<<<<<<<<<<<
@@ -8021,7 +8243,7 @@ static std::string __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchai
   int __pyx_clineno = 0;
   __Pyx_RefNannySetupContext("hash_data", 0);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":409
+  /* "dopt_pollublock_blockchain/blockchain.pyx":420
  *             unsigned char *data_digest
  *             size_t digest_size
  *         data_str = data.encode("UTF-8")             # <<<<<<<<<<<<<<
@@ -8035,24 +8257,24 @@ static std::string __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchai
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     __Pyx_XDECREF(__pyx_t_2); __pyx_t_2 = 0;
-    if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 409, __pyx_L1_error)
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-  __pyx_t_4 = __pyx_convert_string_from_py_6libcpp_6string_std__in_string(__pyx_t_1); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 409, __pyx_L1_error)
+  __pyx_t_4 = __pyx_convert_string_from_py_6libcpp_6string_std__in_string(__pyx_t_1); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 420, __pyx_L1_error)
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":410
+  /* "dopt_pollublock_blockchain/blockchain.pyx":421
  *             size_t digest_size
  *         data_str = data.encode("UTF-8")
  *         data_digest = SHA256_digest(data_str.c_str(), data_str.size(), &digest_size)             # <<<<<<<<<<<<<<
  *         if data_digest is NULL:
  *             raise RuntimeError("Failed to hash data")
 */
-  __pyx_t_5 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_digest(__pyx_v_data_str.c_str(), __pyx_v_data_str.size(), (&__pyx_v_digest_size)); if (unlikely(__pyx_t_5 == ((void *)NULL) && PyErr_Occurred())) __PYX_ERR(0, 410, __pyx_L1_error)
+  __pyx_t_5 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_SHA256_digest(__pyx_v_data_str.c_str(), __pyx_v_data_str.size(), (&__pyx_v_digest_size)); if (unlikely(__pyx_t_5 == ((void *)NULL) && PyErr_Occurred())) __PYX_ERR(0, 421, __pyx_L1_error)
   __pyx_v_data_digest = __pyx_t_5;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":411
+  /* "dopt_pollublock_blockchain/blockchain.pyx":422
  *         data_str = data.encode("UTF-8")
  *         data_digest = SHA256_digest(data_str.c_str(), data_str.size(), &digest_size)
  *         if data_digest is NULL:             # <<<<<<<<<<<<<<
@@ -8062,7 +8284,7 @@ static std::string __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchai
   __pyx_t_6 = (__pyx_v_data_digest == NULL);
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":412
+    /* "dopt_pollublock_blockchain/blockchain.pyx":423
  *         data_digest = SHA256_digest(data_str.c_str(), data_str.size(), &digest_size)
  *         if data_digest is NULL:
  *             raise RuntimeError("Failed to hash data")             # <<<<<<<<<<<<<<
@@ -8075,14 +8297,14 @@ static std::string __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchai
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       __pyx_t_1 = __Pyx_PyObject_FastCall((PyObject*)(((PyTypeObject*)PyExc_RuntimeError)), __pyx_callargs+__pyx_t_3, (2-__pyx_t_3) | (__pyx_t_3*__Pyx_PY_VECTORCALL_ARGUMENTS_OFFSET));
       __Pyx_XDECREF(__pyx_t_2); __pyx_t_2 = 0;
-      if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 412, __pyx_L1_error)
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     __Pyx_DECREF(__pyx_t_1); __pyx_t_1 = 0;
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":411
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@@ -8091,7 +8313,7 @@ static std::string __pyx_f_26dopt_pollublock_blockchain_10blockchain_10Blockchai
 */
   }
 
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":434
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":441
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":439
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":446
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":447
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":449
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":453
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":451
+  /* "dopt_pollublock_blockchain/blockchain.pyx":462
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  *     @property             # <<<<<<<<<<<<<<
@@ -8798,7 +9020,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-/* "dopt_pollublock_blockchain/blockchain.pyx":455
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":457
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":455
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":460
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":463
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":464
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":465
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+    __pyx_t_2 = ((PyObject *)__pyx_vtabptr_26dopt_pollublock_blockchain_10blockchain_PyBlock->from_ptr(__pyx_v_block, NULL)); if (unlikely(!__pyx_t_2)) __PYX_ERR(0, 476, __pyx_L1_error)
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":466
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":467
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     (void)((__pyx_v_it++));
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":459
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 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":469
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@@ -9202,14 +9424,14 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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@@ -9230,7 +9452,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":479
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@@ -9239,19 +9461,19 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":480
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+    __pyx_t_2 = ((PyObject *)__pyx_vtabptr_26dopt_pollublock_blockchain_10blockchain_PyBlock->from_ptr(__pyx_v_block, NULL)); if (unlikely(!__pyx_t_2)) __PYX_ERR(0, 491, __pyx_L1_error)
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":481
+    /* "dopt_pollublock_blockchain/blockchain.pyx":492
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@@ -9264,12 +9486,12 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":482
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@@ -9278,7 +9500,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":483
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-      /* "dopt_pollublock_blockchain/blockchain.pyx":484
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-      /* "dopt_pollublock_blockchain/blockchain.pyx":483
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@@ -9308,7 +9530,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":488
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-      if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 488, __pyx_L1_error)
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":487
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 */
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":490
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+  __pyx_t_7 = ((struct __pyx_vtabstruct_26dopt_pollublock_blockchain_10blockchain_Blockchain *)__pyx_v_self->__pyx_vtab)->get_block_c(__pyx_v_self, __pyx_t_6); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 501, __pyx_L1_error)
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":491
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  *         cdef Block *block = self.get_block_c(idx)
  *         if block is NULL:             # <<<<<<<<<<<<<<
@@ -9516,7 +9738,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
   __pyx_t_1 = (__pyx_v_block == NULL);
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":492
+    /* "dopt_pollublock_blockchain/blockchain.pyx":503
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-      if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 492, __pyx_L1_error)
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":491
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  *         cdef Block *block = self.get_block_c(idx)
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@@ -9545,7 +9767,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":493
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@@ -9555,13 +9777,13 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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+  __pyx_t_4 = ((PyObject *)__pyx_vtabptr_26dopt_pollublock_blockchain_10blockchain_PyBlock->from_ptr(__pyx_v_block, &__pyx_t_8)); if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 504, __pyx_L1_error)
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":486
+  /* "dopt_pollublock_blockchain/blockchain.pyx":497
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  * 
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@@ -9581,7 +9803,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
   return __pyx_r;
 }
 
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@@ -9652,7 +9874,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
   int __pyx_clineno = 0;
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":496
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@@ -9661,7 +9883,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
   if (unlikely(__pyx_v_self->_genesis_done)) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":497
+    /* "dopt_pollublock_blockchain/blockchain.pyx":508
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@@ -9674,14 +9896,14 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-      if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 497, __pyx_L1_error)
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-    __PYX_ERR(0, 497, __pyx_L1_error)
+    __PYX_ERR(0, 508, __pyx_L1_error)
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":496
+    /* "dopt_pollublock_blockchain/blockchain.pyx":507
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@@ -9690,7 +9912,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":502
+  /* "dopt_pollublock_blockchain/blockchain.pyx":513
  *             )
  * 
  *         genesis_prev_hash = ("0" * 64).encode("UTF-8")             # <<<<<<<<<<<<<<
@@ -9700,44 +9922,44 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
   __Pyx_INCREF(__pyx_mstate_global->__pyx_kp_b_00000000000000000000000000000000);
   __pyx_v_genesis_prev_hash = __pyx_mstate_global->__pyx_kp_b_00000000000000000000000000000000;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":503
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  * 
  *         genesis_prev_hash = ("0" * 64).encode("UTF-8")
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-  __pyx_t_4 = ((struct __pyx_vtabstruct_26dopt_pollublock_blockchain_10blockchain_Blockchain *)__pyx_v_self->__pyx_vtab)->hash_data(__pyx_v_self, __pyx_mstate_global->__pyx_kp_u_Genesis_Block); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 503, __pyx_L1_error)
+  __pyx_t_4 = ((struct __pyx_vtabstruct_26dopt_pollublock_blockchain_10blockchain_Blockchain *)__pyx_v_self->__pyx_vtab)->hash_data(__pyx_v_self, __pyx_mstate_global->__pyx_kp_u_Genesis_Block); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 514, __pyx_L1_error)
   __pyx_v_data_str = __PYX_STD_MOVE_IF_SUPPORTED(__pyx_t_4);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":507
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  *             current_timestamp_integer(),             # <<<<<<<<<<<<<<
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-  __pyx_t_5 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_current_timestamp_integer(); if (unlikely(__pyx_t_5 == ((uint64_t)-1LL) && PyErr_Occurred())) __PYX_ERR(0, 507, __pyx_L1_error)
+  __pyx_t_5 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_current_timestamp_integer(); if (unlikely(__pyx_t_5 == ((uint64_t)-1LL) && PyErr_Occurred())) __PYX_ERR(0, 518, __pyx_L1_error)
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":510
+  /* "dopt_pollublock_blockchain/blockchain.pyx":521
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 */
-  __pyx_t_4 = __pyx_convert_string_from_py_6libcpp_6string_std__in_string(__pyx_v_genesis_prev_hash); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 510, __pyx_L1_error)
+  __pyx_t_4 = __pyx_convert_string_from_py_6libcpp_6string_std__in_string(__pyx_v_genesis_prev_hash); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 521, __pyx_L1_error)
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":511
+  /* "dopt_pollublock_blockchain/blockchain.pyx":522
  *             data_str,
  *             genesis_prev_hash,
  *             "".encode("UTF-8"),             # <<<<<<<<<<<<<<
  *         )
  *         cdef int res = self.add_block(block)
 */
-  __pyx_t_6 = __pyx_convert_string_from_py_6libcpp_6string_std__in_string(__pyx_mstate_global->__pyx_kp_b_); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 511, __pyx_L1_error)
+  __pyx_t_6 = __pyx_convert_string_from_py_6libcpp_6string_std__in_string(__pyx_mstate_global->__pyx_kp_b_); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 522, __pyx_L1_error)
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":505
+  /* "dopt_pollublock_blockchain/blockchain.pyx":516
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  * 
  *         cdef Block *block = new Block(             # <<<<<<<<<<<<<<
@@ -9748,21 +9970,21 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":513
+  /* "dopt_pollublock_blockchain/blockchain.pyx":524
  *             "".encode("UTF-8"),
  *         )
  *         cdef int res = self.add_block(block)             # <<<<<<<<<<<<<<
  *         if res != 0:
  *             raise RuntimeError("Could not mine block. No nonce found")
 */
-  __pyx_t_8 = ((struct __pyx_vtabstruct_26dopt_pollublock_blockchain_10blockchain_Blockchain *)__pyx_v_self->__pyx_vtab)->add_block(__pyx_v_self, __pyx_v_block); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 513, __pyx_L1_error)
+  __pyx_t_8 = ((struct __pyx_vtabstruct_26dopt_pollublock_blockchain_10blockchain_Blockchain *)__pyx_v_self->__pyx_vtab)->add_block(__pyx_v_self, __pyx_v_block); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 524, __pyx_L1_error)
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":514
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@@ -9772,7 +9994,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
   __pyx_t_9 = (__pyx_v_res != 0);
   if (unlikely(__pyx_t_9)) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":515
+    /* "dopt_pollublock_blockchain/blockchain.pyx":526
  *         cdef int res = self.add_block(block)
  *         if res != 0:
  *             raise RuntimeError("Could not mine block. No nonce found")             # <<<<<<<<<<<<<<
@@ -9785,14 +10007,14 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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       __pyx_t_1 = __Pyx_PyObject_FastCall((PyObject*)(((PyTypeObject*)PyExc_RuntimeError)), __pyx_callargs+__pyx_t_3, (2-__pyx_t_3) | (__pyx_t_3*__Pyx_PY_VECTORCALL_ARGUMENTS_OFFSET));
       __Pyx_XDECREF(__pyx_t_2); __pyx_t_2 = 0;
-      if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 515, __pyx_L1_error)
+      if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 526, __pyx_L1_error)
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     __Pyx_Raise(__pyx_t_1, 0, 0, 0);
     __Pyx_DECREF(__pyx_t_1); __pyx_t_1 = 0;
-    __PYX_ERR(0, 515, __pyx_L1_error)
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":514
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@@ -9801,7 +10023,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":516
+  /* "dopt_pollublock_blockchain/blockchain.pyx":527
  *         if res != 0:
  *             raise RuntimeError("Could not mine block. No nonce found")
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@@ -9810,7 +10032,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
   __pyx_v_self->_genesis_done = 1;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":495
+  /* "dopt_pollublock_blockchain/blockchain.pyx":506
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  *     def create_genesis_block(self):             # <<<<<<<<<<<<<<
@@ -9833,7 +10055,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":518
+/* "dopt_pollublock_blockchain/blockchain.pyx":529
  *         self._genesis_done = True
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  *     def new_block(self, data):             # <<<<<<<<<<<<<<
@@ -9880,32 +10102,32 @@ PyObject *__pyx_args, PyObject *__pyx_kwds
   {
     PyObject ** const __pyx_pyargnames[] = {&__pyx_mstate_global->__pyx_n_u_data,0};
     const Py_ssize_t __pyx_kwds_len = (__pyx_kwds) ? __Pyx_NumKwargs_FASTCALL(__pyx_kwds) : 0;
-    if (unlikely(__pyx_kwds_len) < 0) __PYX_ERR(0, 518, __pyx_L3_error)
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     if (__pyx_kwds_len > 0) {
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-  __Pyx_RaiseArgtupleInvalid("new_block", 1, 1, 1, __pyx_nargs); __PYX_ERR(0, 518, __pyx_L3_error)
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@@ -9949,7 +10171,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":527
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@@ -9959,7 +10181,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":528
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  *         if not self._genesis_done:
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@@ -9972,14 +10194,14 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-      if (unlikely(!__pyx_t_2)) __PYX_ERR(0, 528, __pyx_L1_error)
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":527
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  *         if not self._genesis_done:             # <<<<<<<<<<<<<<
@@ -9988,7 +10210,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":529
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":530
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+    __PYX_ERR(0, 541, __pyx_L1_error)
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":529
+    /* "dopt_pollublock_blockchain/blockchain.pyx":540
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  *         if not isinstance(data, str):             # <<<<<<<<<<<<<<
@@ -10028,27 +10250,27 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":532
+  /* "dopt_pollublock_blockchain/blockchain.pyx":543
  *             raise TypeError("Data must be a string")
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+  __pyx_t_6 = ((struct __pyx_vtabstruct_26dopt_pollublock_blockchain_10blockchain_Blockchain *)__pyx_v_self->__pyx_vtab)->hash_data(__pyx_v_self, __pyx_v_data); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 543, __pyx_L1_error)
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":533
+  /* "dopt_pollublock_blockchain/blockchain.pyx":544
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  *         prev_block = self.get_block_c(self._index)             # <<<<<<<<<<<<<<
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-  __pyx_t_7 = ((struct __pyx_vtabstruct_26dopt_pollublock_blockchain_10blockchain_Blockchain *)__pyx_v_self->__pyx_vtab)->get_block_c(__pyx_v_self, __pyx_v_self->_index); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 533, __pyx_L1_error)
+  __pyx_t_7 = ((struct __pyx_vtabstruct_26dopt_pollublock_blockchain_10blockchain_Blockchain *)__pyx_v_self->__pyx_vtab)->get_block_c(__pyx_v_self, __pyx_v_self->_index); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 544, __pyx_L1_error)
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":534
+  /* "dopt_pollublock_blockchain/blockchain.pyx":545
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  *         prev_hash = prev_block.hash             # <<<<<<<<<<<<<<
@@ -10058,7 +10280,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":535
+  /* "dopt_pollublock_blockchain/blockchain.pyx":546
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  *         new_idx = self._index + 1             # <<<<<<<<<<<<<<
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":539
+  /* "dopt_pollublock_blockchain/blockchain.pyx":550
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+  __pyx_t_8 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_current_timestamp_integer(); if (unlikely(__pyx_t_8 == ((uint64_t)-1LL) && PyErr_Occurred())) __PYX_ERR(0, 550, __pyx_L1_error)
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":543
+  /* "dopt_pollublock_blockchain/blockchain.pyx":554
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":537
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  * 
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@@ -10096,21 +10318,21 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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+  /* "dopt_pollublock_blockchain/blockchain.pyx":556
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-  __pyx_t_9 = ((struct __pyx_vtabstruct_26dopt_pollublock_blockchain_10blockchain_Blockchain *)__pyx_v_self->__pyx_vtab)->add_block(__pyx_v_self, __pyx_v_block); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 545, __pyx_L1_error)
+  __pyx_t_9 = ((struct __pyx_vtabstruct_26dopt_pollublock_blockchain_10blockchain_Blockchain *)__pyx_v_self->__pyx_vtab)->add_block(__pyx_v_self, __pyx_v_block); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 556, __pyx_L1_error)
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":546
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@@ -10120,7 +10342,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":547
+    /* "dopt_pollublock_blockchain/blockchain.pyx":558
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  *             raise RuntimeError("Could not mine block. No nonce found")             # <<<<<<<<<<<<<<
@@ -10133,14 +10355,14 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-      if (unlikely(!__pyx_t_2)) __PYX_ERR(0, 547, __pyx_L1_error)
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":549
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":518
+  /* "dopt_pollublock_blockchain/blockchain.pyx":529
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  * 
  *     def new_block(self, data):             # <<<<<<<<<<<<<<
@@ -10183,7 +10405,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":551
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@@ -10259,7 +10481,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-  /* "dopt_pollublock_blockchain/blockchain.pyx":554
+  /* "dopt_pollublock_blockchain/blockchain.pyx":565
  *         cdef:
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  *             Block *prev_block = NULL             # <<<<<<<<<<<<<<
@@ -10268,7 +10490,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
   __pyx_v_prev_block = NULL;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":555
+  /* "dopt_pollublock_blockchain/blockchain.pyx":566
  *             Block *block
  *             Block *prev_block = NULL
  *             int idx = 0             # <<<<<<<<<<<<<<
@@ -10277,7 +10499,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
   __pyx_v_idx = 0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":559
+  /* "dopt_pollublock_blockchain/blockchain.pyx":570
  *             size_t digest_size
  * 
  *         for idx in range(self._chain[0].size()):             # <<<<<<<<<<<<<<
@@ -10289,7 +10511,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":560
+    /* "dopt_pollublock_blockchain/blockchain.pyx":571
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  *         for idx in range(self._chain[0].size()):
  *             block = self._chain[0][idx]             # <<<<<<<<<<<<<<
@@ -10298,7 +10520,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
     __pyx_v_block = ((__pyx_v_self->_chain[0])[__pyx_v_idx]);
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":561
+    /* "dopt_pollublock_blockchain/blockchain.pyx":572
  *         for idx in range(self._chain[0].size()):
  *             block = self._chain[0][idx]
  *             py_bytes = bytes.fromhex(block.hash.decode("UTF-8"))             # <<<<<<<<<<<<<<
@@ -10307,7 +10529,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
     __pyx_t_5 = ((PyObject *)(&PyBytes_Type));
     __Pyx_INCREF(__pyx_t_5);
-    __pyx_t_6 = __Pyx_decode_cpp_string(__pyx_v_block->hash, 0, PY_SSIZE_T_MAX, NULL, NULL, PyUnicode_DecodeUTF8); if (unlikely(!__pyx_t_6)) __PYX_ERR(0, 561, __pyx_L1_error)
+    __pyx_t_6 = __Pyx_decode_cpp_string(__pyx_v_block->hash, 0, PY_SSIZE_T_MAX, NULL, NULL, PyUnicode_DecodeUTF8); if (unlikely(!__pyx_t_6)) __PYX_ERR(0, 572, __pyx_L1_error)
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@@ -10315,23 +10537,23 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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     __pyx_t_4 = 0;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":562
+    /* "dopt_pollublock_blockchain/blockchain.pyx":573
  *             block = self._chain[0][idx]
  *             py_bytes = bytes.fromhex(block.hash.decode("UTF-8"))
  *             digest = perform_hash_c(block, &digest_size)             # <<<<<<<<<<<<<<
  *             py_bytes_rehashed = bytes(digest[:digest_size])
  *             free(digest)
 */
-    __pyx_t_8 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_perform_hash_c(__pyx_v_block, (&__pyx_v_digest_size)); if (unlikely(__pyx_t_8 == ((void *)NULL) && PyErr_Occurred())) __PYX_ERR(0, 562, __pyx_L1_error)
+    __pyx_t_8 = __pyx_f_26dopt_pollublock_blockchain_10blockchain_perform_hash_c(__pyx_v_block, (&__pyx_v_digest_size)); if (unlikely(__pyx_t_8 == ((void *)NULL) && PyErr_Occurred())) __PYX_ERR(0, 573, __pyx_L1_error)
     __pyx_v_digest = __pyx_t_8;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":563
+    /* "dopt_pollublock_blockchain/blockchain.pyx":574
  *             py_bytes = bytes.fromhex(block.hash.decode("UTF-8"))
  *             digest = perform_hash_c(block, &digest_size)
  *             py_bytes_rehashed = bytes(digest[:digest_size])             # <<<<<<<<<<<<<<
@@ -10339,7 +10561,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
  *             if py_bytes != py_bytes_rehashed:
 */
     __pyx_t_6 = NULL;
-    __pyx_t_5 = __Pyx_PyBytes_FromStringAndSize(((char const *)__pyx_v_digest) + 0, __pyx_v_digest_size - 0); if (unlikely(!__pyx_t_5)) __PYX_ERR(0, 563, __pyx_L1_error)
+    __pyx_t_5 = __Pyx_PyBytes_FromStringAndSize(((char const *)__pyx_v_digest) + 0, __pyx_v_digest_size - 0); if (unlikely(!__pyx_t_5)) __PYX_ERR(0, 574, __pyx_L1_error)
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@@ -10347,13 +10569,13 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
       __pyx_t_4 = __Pyx_PyObject_FastCall((PyObject*)(&PyBytes_Type), __pyx_callargs+__pyx_t_7, (2-__pyx_t_7) | (__pyx_t_7*__Pyx_PY_VECTORCALL_ARGUMENTS_OFFSET));
       __Pyx_XDECREF(__pyx_t_6); __pyx_t_6 = 0;
       __Pyx_DECREF(__pyx_t_5); __pyx_t_5 = 0;
-      if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 563, __pyx_L1_error)
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     __pyx_t_4 = 0;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":564
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 */
     free(__pyx_v_digest);
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":565
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+    __pyx_t_9 = (__Pyx_PyBytes_Equals(__pyx_v_py_bytes, __pyx_v_py_bytes_rehashed, Py_NE)); if (unlikely((__pyx_t_9 < 0))) __PYX_ERR(0, 576, __pyx_L1_error)
     if (__pyx_t_9) {
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":566
+      /* "dopt_pollublock_blockchain/blockchain.pyx":577
  *             free(digest)
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  *                 print(f"Index {idx}: Hashes to not match. Abort.")             # <<<<<<<<<<<<<<
@@ -10380,13 +10602,13 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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 */
       __pyx_t_5 = NULL;
-      __pyx_t_6 = __Pyx_PyUnicode_From_int(__pyx_v_idx, 0, ' ', 'd'); if (unlikely(!__pyx_t_6)) __PYX_ERR(0, 566, __pyx_L1_error)
+      __pyx_t_6 = __Pyx_PyUnicode_From_int(__pyx_v_idx, 0, ' ', 'd'); if (unlikely(!__pyx_t_6)) __PYX_ERR(0, 577, __pyx_L1_error)
       __Pyx_GOTREF(__pyx_t_6);
-      __pyx_t_10[0] = __pyx_mstate_global->__pyx_kp_u_Index;
+      __pyx_t_10[0] = __pyx_mstate_global->__pyx_kp_u_Index_2;
       __pyx_t_10[1] = __pyx_t_6;
       __pyx_t_10[2] = __pyx_mstate_global->__pyx_kp_u_Hashes_to_not_match_Abort;
       __pyx_t_11 = __Pyx_PyUnicode_Join(__pyx_t_10, 3, 6 + __Pyx_PyUnicode_GET_LENGTH(__pyx_t_6) + 29, 127);
-      if (unlikely(!__pyx_t_11)) __PYX_ERR(0, 566, __pyx_L1_error)
+      if (unlikely(!__pyx_t_11)) __PYX_ERR(0, 577, __pyx_L1_error)
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@@ -10395,12 +10617,12 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
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-        if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 566, __pyx_L1_error)
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-      /* "dopt_pollublock_blockchain/blockchain.pyx":567
+      /* "dopt_pollublock_blockchain/blockchain.pyx":578
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  *                 return False             # <<<<<<<<<<<<<<
@@ -10412,7 +10634,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
       __pyx_r = Py_False;
       goto __pyx_L0;
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":565
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  *             free(digest)
  *             if py_bytes != py_bytes_rehashed:             # <<<<<<<<<<<<<<
@@ -10421,7 +10643,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
     }
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":568
+    /* "dopt_pollublock_blockchain/blockchain.pyx":579
  *                 print(f"Index {idx}: Hashes to not match. Abort.")
  *                 return False
  *             if prev_block is not NULL:             # <<<<<<<<<<<<<<
@@ -10431,7 +10653,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
     __pyx_t_9 = (__pyx_v_prev_block != NULL);
     if (__pyx_t_9) {
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":569
+      /* "dopt_pollublock_blockchain/blockchain.pyx":580
  *                 return False
  *             if prev_block is not NULL:
  *                 if prev_block.hash != block.prev_hash:             # <<<<<<<<<<<<<<
@@ -10441,7 +10663,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
       __pyx_t_9 = (__pyx_v_prev_block->hash != __pyx_v_block->prev_hash);
       if (__pyx_t_9) {
 
-        /* "dopt_pollublock_blockchain/blockchain.pyx":570
+        /* "dopt_pollublock_blockchain/blockchain.pyx":581
  *             if prev_block is not NULL:
  *                 if prev_block.hash != block.prev_hash:
  *                     print(             # <<<<<<<<<<<<<<
@@ -10450,20 +10672,20 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
         __pyx_t_11 = NULL;
 
-        /* "dopt_pollublock_blockchain/blockchain.pyx":571
+        /* "dopt_pollublock_blockchain/blockchain.pyx":582
  *                 if prev_block.hash != block.prev_hash:
  *                     print(
  *                         (f"Index {idx}: Hash mismatch. Hash of previous block does not "             # <<<<<<<<<<<<<<
  *                         "match the saved one in the current block. Abort.")
  *                     )
 */
-        __pyx_t_5 = __Pyx_PyUnicode_From_int(__pyx_v_idx, 0, ' ', 'd'); if (unlikely(!__pyx_t_5)) __PYX_ERR(0, 571, __pyx_L1_error)
+        __pyx_t_5 = __Pyx_PyUnicode_From_int(__pyx_v_idx, 0, ' ', 'd'); if (unlikely(!__pyx_t_5)) __PYX_ERR(0, 582, __pyx_L1_error)
         __Pyx_GOTREF(__pyx_t_5);
-        __pyx_t_10[0] = __pyx_mstate_global->__pyx_kp_u_Index;
+        __pyx_t_10[0] = __pyx_mstate_global->__pyx_kp_u_Index_2;
         __pyx_t_10[1] = __pyx_t_5;
         __pyx_t_10[2] = __pyx_mstate_global->__pyx_kp_u_Hash_mismatch_Hash_of_previous;
         __pyx_t_6 = __Pyx_PyUnicode_Join(__pyx_t_10, 3, 6 + __Pyx_PyUnicode_GET_LENGTH(__pyx_t_5) + 97, 127);
-        if (unlikely(!__pyx_t_6)) __PYX_ERR(0, 571, __pyx_L1_error)
+        if (unlikely(!__pyx_t_6)) __PYX_ERR(0, 582, __pyx_L1_error)
         __Pyx_GOTREF(__pyx_t_6);
         __Pyx_DECREF(__pyx_t_5); __pyx_t_5 = 0;
         __pyx_t_7 = 1;
@@ -10472,12 +10694,12 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
           __pyx_t_4 = __Pyx_PyObject_FastCall((PyObject*)__pyx_builtin_print, __pyx_callargs+__pyx_t_7, (2-__pyx_t_7) | (__pyx_t_7*__Pyx_PY_VECTORCALL_ARGUMENTS_OFFSET));
           __Pyx_XDECREF(__pyx_t_11); __pyx_t_11 = 0;
           __Pyx_DECREF(__pyx_t_6); __pyx_t_6 = 0;
-          if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 570, __pyx_L1_error)
+          if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 581, __pyx_L1_error)
           __Pyx_GOTREF(__pyx_t_4);
         }
         __Pyx_DECREF(__pyx_t_4); __pyx_t_4 = 0;
 
-        /* "dopt_pollublock_blockchain/blockchain.pyx":574
+        /* "dopt_pollublock_blockchain/blockchain.pyx":585
  *                         "match the saved one in the current block. Abort.")
  *                     )
  *                     return False             # <<<<<<<<<<<<<<
@@ -10489,7 +10711,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
         __pyx_r = Py_False;
         goto __pyx_L0;
 
-        /* "dopt_pollublock_blockchain/blockchain.pyx":569
+        /* "dopt_pollublock_blockchain/blockchain.pyx":580
  *                 return False
  *             if prev_block is not NULL:
  *                 if prev_block.hash != block.prev_hash:             # <<<<<<<<<<<<<<
@@ -10498,7 +10720,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
       }
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":568
+      /* "dopt_pollublock_blockchain/blockchain.pyx":579
  *                 print(f"Index {idx}: Hashes to not match. Abort.")
  *                 return False
  *             if prev_block is not NULL:             # <<<<<<<<<<<<<<
@@ -10507,7 +10729,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
     }
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":575
+    /* "dopt_pollublock_blockchain/blockchain.pyx":586
  *                     )
  *                     return False
  *             prev_block = block             # <<<<<<<<<<<<<<
@@ -10517,7 +10739,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
     __pyx_v_prev_block = __pyx_v_block;
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":577
+  /* "dopt_pollublock_blockchain/blockchain.pyx":588
  *             prev_block = block
  * 
  *         return True             # <<<<<<<<<<<<<<
@@ -10529,7 +10751,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
   __pyx_r = Py_True;
   goto __pyx_L0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":551
+  /* "dopt_pollublock_blockchain/blockchain.pyx":562
  *         return self._index
  * 
  *     def validate(self):             # <<<<<<<<<<<<<<
@@ -10553,7 +10775,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
   return __pyx_r;
 }
 
-/* "dopt_pollublock_blockchain/blockchain.pyx":579
+/* "dopt_pollublock_blockchain/blockchain.pyx":590
  *         return True
  * 
  *     def get_saving_entries(self, min_idx):             # <<<<<<<<<<<<<<
@@ -10600,32 +10822,32 @@ PyObject *__pyx_args, PyObject *__pyx_kwds
   {
     PyObject ** const __pyx_pyargnames[] = {&__pyx_mstate_global->__pyx_n_u_min_idx,0};
     const Py_ssize_t __pyx_kwds_len = (__pyx_kwds) ? __Pyx_NumKwargs_FASTCALL(__pyx_kwds) : 0;
-    if (unlikely(__pyx_kwds_len) < 0) __PYX_ERR(0, 579, __pyx_L3_error)
+    if (unlikely(__pyx_kwds_len) < 0) __PYX_ERR(0, 590, __pyx_L3_error)
     if (__pyx_kwds_len > 0) {
       switch (__pyx_nargs) {
         case  1:
         values[0] = __Pyx_ArgRef_FASTCALL(__pyx_args, 0);
-        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[0])) __PYX_ERR(0, 579, __pyx_L3_error)
+        if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[0])) __PYX_ERR(0, 590, __pyx_L3_error)
         CYTHON_FALLTHROUGH;
         case  0: break;
         default: goto __pyx_L5_argtuple_error;
       }
       const Py_ssize_t kwd_pos_args = __pyx_nargs;
-      if (__Pyx_ParseKeywords(__pyx_kwds, __pyx_kwvalues, __pyx_pyargnames, 0, values, kwd_pos_args, __pyx_kwds_len, "get_saving_entries", 0) < (0)) __PYX_ERR(0, 579, __pyx_L3_error)
+      if (__Pyx_ParseKeywords(__pyx_kwds, __pyx_kwvalues, __pyx_pyargnames, 0, values, kwd_pos_args, __pyx_kwds_len, "get_saving_entries", 0) < (0)) __PYX_ERR(0, 590, __pyx_L3_error)
       for (Py_ssize_t i = __pyx_nargs; i < 1; i++) {
-        if (unlikely(!values[i])) { __Pyx_RaiseArgtupleInvalid("get_saving_entries", 1, 1, 1, i); __PYX_ERR(0, 579, __pyx_L3_error) }
+        if (unlikely(!values[i])) { __Pyx_RaiseArgtupleInvalid("get_saving_entries", 1, 1, 1, i); __PYX_ERR(0, 590, __pyx_L3_error) }
       }
     } else if (unlikely(__pyx_nargs != 1)) {
       goto __pyx_L5_argtuple_error;
     } else {
       values[0] = __Pyx_ArgRef_FASTCALL(__pyx_args, 0);
-      if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[0])) __PYX_ERR(0, 579, __pyx_L3_error)
+      if (!CYTHON_ASSUME_SAFE_MACROS && unlikely(!values[0])) __PYX_ERR(0, 590, __pyx_L3_error)
     }
     __pyx_v_min_idx = values[0];
   }
   goto __pyx_L6_skip;
   __pyx_L5_argtuple_error:;
-  __Pyx_RaiseArgtupleInvalid("get_saving_entries", 1, 1, 1, __pyx_nargs); __PYX_ERR(0, 579, __pyx_L3_error)
+  __Pyx_RaiseArgtupleInvalid("get_saving_entries", 1, 1, 1, __pyx_nargs); __PYX_ERR(0, 590, __pyx_L3_error)
   __pyx_L6_skip:;
   goto __pyx_L4_argument_unpacking_done;
   __pyx_L3_error:;
@@ -10665,19 +10887,19 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
   int __pyx_clineno = 0;
   __Pyx_RefNannySetupContext("get_saving_entries", 0);
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":580
+  /* "dopt_pollublock_blockchain/blockchain.pyx":591
  * 
  *     def get_saving_entries(self, min_idx):
  *         entries = []             # <<<<<<<<<<<<<<
  *         cdef:
  *             Block *block
 */
-  __pyx_t_1 = PyList_New(0); if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 580, __pyx_L1_error)
+  __pyx_t_1 = PyList_New(0); if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 591, __pyx_L1_error)
   __Pyx_GOTREF(__pyx_t_1);
   __pyx_v_entries = ((PyObject*)__pyx_t_1);
   __pyx_t_1 = 0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":583
+  /* "dopt_pollublock_blockchain/blockchain.pyx":594
  *         cdef:
  *             Block *block
  *             int idx = 0             # <<<<<<<<<<<<<<
@@ -10686,7 +10908,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
   __pyx_v_idx = 0;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":586
+  /* "dopt_pollublock_blockchain/blockchain.pyx":597
  *             int _min_idx
  * 
  *         if min_idx is None:             # <<<<<<<<<<<<<<
@@ -10696,7 +10918,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
   __pyx_t_2 = (__pyx_v_min_idx == Py_None);
   if (__pyx_t_2) {
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":587
+    /* "dopt_pollublock_blockchain/blockchain.pyx":598
  * 
  *         if min_idx is None:
  *             _min_idx = -1             # <<<<<<<<<<<<<<
@@ -10705,7 +10927,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
     __pyx_v__min_idx = -1;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":586
+    /* "dopt_pollublock_blockchain/blockchain.pyx":597
  *             int _min_idx
  * 
  *         if min_idx is None:             # <<<<<<<<<<<<<<
@@ -10715,7 +10937,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
     goto __pyx_L3;
   }
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":589
+  /* "dopt_pollublock_blockchain/blockchain.pyx":600
  *             _min_idx = -1
  *         else:
  *             _min_idx = min_idx             # <<<<<<<<<<<<<<
@@ -10723,12 +10945,12 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
  *         for idx in range(self._chain[0].size()):
 */
   /*else*/ {
-    __pyx_t_3 = __Pyx_PyLong_As_int(__pyx_v_min_idx); if (unlikely((__pyx_t_3 == (int)-1) && PyErr_Occurred())) __PYX_ERR(0, 589, __pyx_L1_error)
+    __pyx_t_3 = __Pyx_PyLong_As_int(__pyx_v_min_idx); if (unlikely((__pyx_t_3 == (int)-1) && PyErr_Occurred())) __PYX_ERR(0, 600, __pyx_L1_error)
     __pyx_v__min_idx = __pyx_t_3;
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   __pyx_L3:;
 
-  /* "dopt_pollublock_blockchain/blockchain.pyx":591
+  /* "dopt_pollublock_blockchain/blockchain.pyx":602
  *             _min_idx = min_idx
  * 
  *         for idx in range(self._chain[0].size()):             # <<<<<<<<<<<<<<
@@ -10740,7 +10962,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
   for (__pyx_t_3 = 0; __pyx_t_3 < __pyx_t_5; __pyx_t_3+=1) {
     __pyx_v_idx = __pyx_t_3;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":592
+    /* "dopt_pollublock_blockchain/blockchain.pyx":603
  * 
  *         for idx in range(self._chain[0].size()):
  *             if idx <= _min_idx:             # <<<<<<<<<<<<<<
@@ -10750,7 +10972,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
     __pyx_t_2 = (__pyx_v_idx <= __pyx_v__min_idx);
     if (__pyx_t_2) {
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":593
+      /* "dopt_pollublock_blockchain/blockchain.pyx":604
  *         for idx in range(self._chain[0].size()):
  *             if idx <= _min_idx:
  *                 continue             # <<<<<<<<<<<<<<
@@ -10759,7 +10981,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
       goto __pyx_L4_continue;
 
-      /* "dopt_pollublock_blockchain/blockchain.pyx":592
+      /* "dopt_pollublock_blockchain/blockchain.pyx":603
  * 
  *         for idx in range(self._chain[0].size()):
  *             if idx <= _min_idx:             # <<<<<<<<<<<<<<
@@ -10768,7 +10990,7 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
     }
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":594
+    /* "dopt_pollublock_blockchain/blockchain.pyx":605
  *             if idx <= _min_idx:
  *                 continue
  *             block = self._chain[0][idx]             # <<<<<<<<<<<<<<
@@ -10777,102 +10999,102 @@ static PyObject *__pyx_pf_26dopt_pollublock_blockchain_10blockchain_10Blockchain
 */
     __pyx_v_block = ((__pyx_v_self->_chain[0])[__pyx_v_idx]);
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":595
+    /* "dopt_pollublock_blockchain/blockchain.pyx":606
  *                 continue
  *             block = self._chain[0][idx]
  *             contents = {}             # <<<<<<<<<<<<<<
  *             contents["index"] = block.index
  *             contents["timestamp"] = block.timestamp
 */
-    __pyx_t_1 = __Pyx_PyDict_NewPresized(0); if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 595, __pyx_L1_error)
+    __pyx_t_1 = __Pyx_PyDict_NewPresized(0); if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 606, __pyx_L1_error)
     __Pyx_GOTREF(__pyx_t_1);
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     __pyx_t_1 = 0;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":596
+    /* "dopt_pollublock_blockchain/blockchain.pyx":607
  *             block = self._chain[0][idx]
  *             contents = {}
  *             contents["index"] = block.index             # <<<<<<<<<<<<<<
  *             contents["timestamp"] = block.timestamp
  *             contents["nonce"] = block.nonce
 */
-    __pyx_t_1 = __Pyx_PyLong_From_uint64_t(__pyx_v_block->index); if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 596, __pyx_L1_error)
+    __pyx_t_1 = __Pyx_PyLong_From_uint64_t(__pyx_v_block->index); if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 607, __pyx_L1_error)
     __Pyx_GOTREF(__pyx_t_1);
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":597
+    /* "dopt_pollublock_blockchain/blockchain.pyx":608
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  *             contents["index"] = block.index
  *             contents["timestamp"] = block.timestamp             # <<<<<<<<<<<<<<
  *             contents["nonce"] = block.nonce
  *             contents["previous_hash"] = block.prev_hash.decode("UTF-8")
 */
-    __pyx_t_1 = __Pyx_PyLong_From_uint64_t(__pyx_v_block->timestamp); if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 597, __pyx_L1_error)
+    __pyx_t_1 = __Pyx_PyLong_From_uint64_t(__pyx_v_block->timestamp); if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 608, __pyx_L1_error)
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":598
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  *             contents["timestamp"] = block.timestamp
  *             contents["nonce"] = block.nonce             # <<<<<<<<<<<<<<
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  *             contents["hash"] = block.hash.decode("UTF-8")
 */
-    __pyx_t_1 = __Pyx_PyLong_From_uint64_t(__pyx_v_block->nonce); if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 598, __pyx_L1_error)
+    __pyx_t_1 = __Pyx_PyLong_From_uint64_t(__pyx_v_block->nonce); if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 609, __pyx_L1_error)
     __Pyx_GOTREF(__pyx_t_1);
-    if (unlikely((PyDict_SetItem(__pyx_v_contents, __pyx_mstate_global->__pyx_n_u_nonce, __pyx_t_1) < 0))) __PYX_ERR(0, 598, __pyx_L1_error)
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-    /* "dopt_pollublock_blockchain/blockchain.pyx":599
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  *             contents["timestamp"] = block.timestamp
  *             contents["nonce"] = block.nonce
  *             contents["previous_hash"] = block.prev_hash.decode("UTF-8")             # <<<<<<<<<<<<<<
  *             contents["hash"] = block.hash.decode("UTF-8")
  *             contents["data"] = block.data.decode("UTF-8")
 */
-    __pyx_t_1 = __Pyx_decode_cpp_string(__pyx_v_block->prev_hash, 0, PY_SSIZE_T_MAX, NULL, NULL, PyUnicode_DecodeUTF8); if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 599, __pyx_L1_error)
+    __pyx_t_1 = __Pyx_decode_cpp_string(__pyx_v_block->prev_hash, 0, PY_SSIZE_T_MAX, NULL, NULL, PyUnicode_DecodeUTF8); if (unlikely(!__pyx_t_1)) __PYX_ERR(0, 610, __pyx_L1_error)
     __Pyx_GOTREF(__pyx_t_1);
-    if (unlikely((PyDict_SetItem(__pyx_v_contents, __pyx_mstate_global->__pyx_n_u_previous_hash, __pyx_t_1) < 0))) __PYX_ERR(0, 599, __pyx_L1_error)
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     __Pyx_DECREF(__pyx_t_1); __pyx_t_1 = 0;
 
-    /* "dopt_pollublock_blockchain/blockchain.pyx":600
+    /* "dopt_pollublock_blockchain/blockchain.pyx":611
  *             contents["nonce"] = block.nonce
  *             contents["previous_hash"] = block.prev_hash.decode("UTF-8")
  *             contents["hash"] = block.hash.decode("UTF-8")             # <<<<<<<<<<<<<<
  *             contents["data"] = block.data.decode("UTF-8")
  *             entries.append(contents)
 */
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-    PyObject *data = __Pyx_DecompressString(cstring, 1874, 1);
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+    #else /* compression: none (3894 bytes) */
+const char* const bytes = "Blockchain already has a genesis block. Either it was created or loaded.Blockchain was already loadedCould not allocate hasmapCould not allocate vectorCould not mine block. No nonce foundCreate a genesis block first.\n\tData:\t\tData must be a stringDifficulty must be greater than 0Difficulty must be integer valueFailed to hash dataGenesis Block\n\tHash:\t\t: Hash mismatch. Hash of previous block does not match the saved one in the current block. Abort.: Hashes to not match. 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     PyObject *data = NULL;
     CYTHON_UNUSED_VAR(__Pyx_DecompressString);
     #endif
     PyObject **stringtab = __pyx_mstate->__pyx_string_tab;
     Py_ssize_t pos = 0;
-    for (int i = 0; i < 173; i++) {
+    for (int i = 0; i < 183; i++) {
       Py_ssize_t bytes_length = index[i].length;
       PyObject *string = PyUnicode_DecodeUTF8(bytes + pos, bytes_length, NULL);
       if (likely(string) && i >= 36) PyUnicode_InternInPlace(&string);
@@ -13729,7 +13991,7 @@ const char* const bytes = "Blockchain already has a genesis block. Either it was
       stringtab[i] = string;
       pos += bytes_length;
     }
-    for (int i = 173; i < 189; i++) {
+    for (int i = 183; i < 200; i++) {
       Py_ssize_t bytes_length = index[i].length;
       PyObject *string = PyBytes_FromStringAndSize(bytes + pos, bytes_length);
       stringtab[i] = string;
@@ -13740,15 +14002,15 @@ const char* const bytes = "Blockchain already has a genesis block. Either it was
       }
     }
     Py_XDECREF(data);
-    for (Py_ssize_t i = 0; i < 189; i++) {
+    for (Py_ssize_t i = 0; i < 200; i++) {
       if (unlikely(PyObject_Hash(stringtab[i]) == -1)) {
         __PYX_ERR(0, 1, __pyx_L1_error)
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     }
     #if CYTHON_IMMORTAL_CONSTANTS
     {
-      PyObject **table = stringtab + 173;
-      for (Py_ssize_t i=0; i<16; ++i) {
+      PyObject **table = stringtab + 183;
+      for (Py_ssize_t i=0; i<17; ++i) {
         #if CYTHON_COMPILING_IN_CPYTHON_FREETHREADING
         Py_SET_REFCNT(table[i], _Py_IMMORTAL_REFCNT_LOCAL);
         #else
@@ -13806,89 +14068,94 @@ static int __Pyx_CreateCodeObjects(__pyx_mstatetype *__pyx_mstate) {
   PyObject* tuple_dedup_map = PyDict_New();
   if (unlikely(!tuple_dedup_map)) return -1;
   {
-    const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 2, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 145};
-    PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_contents};
-    __pyx_mstate_global->__pyx_codeobj_tab[0] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_serialize_dict, __pyx_mstate->__pyx_kp_b_iso88591_A_1_D_q_G1_D_q_D_4q_4q_q, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[0])) goto bad;
+    const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 1, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 146};
+    PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self};
+    __pyx_mstate_global->__pyx_codeobj_tab[0] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_as_dataclass, __pyx_mstate->__pyx_kp_b_iso88591_A_uL_a_d_a_T_Q_Q, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[0])) goto bad;
   }
   {
-    const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 3, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 182};
-    PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_serialize_res, __pyx_mstate->__pyx_n_u_serialize_size};
-    __pyx_mstate_global->__pyx_codeobj_tab[1] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_bytes_serialize, __pyx_mstate->__pyx_kp_b_iso88591_A_Qd_1A, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[1])) goto bad;
+    const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 2, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 156};
+    PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_contents};
+    __pyx_mstate_global->__pyx_codeobj_tab[1] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_serialize_dict, __pyx_mstate->__pyx_kp_b_iso88591_A_1_D_q_G1_D_q_D_4q_4q_q, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[1])) goto bad;
   }
   {
     const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 3, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 193};
+    PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_serialize_res, __pyx_mstate->__pyx_n_u_serialize_size};
+    __pyx_mstate_global->__pyx_codeobj_tab[2] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_bytes_serialize, __pyx_mstate->__pyx_kp_b_iso88591_A_Qd_1A, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[2])) goto bad;
+  }
+  {
+    const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 3, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 204};
     PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_digest, __pyx_mstate->__pyx_n_u_digest_size};
-    __pyx_mstate_global->__pyx_codeobj_tab[2] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_perform_hash, __pyx_mstate->__pyx_kp_b_iso88591_A_1D_wc_xuAV2_b_q_t1, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[2])) goto bad;
+    __pyx_mstate_global->__pyx_codeobj_tab[3] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_perform_hash, __pyx_mstate->__pyx_kp_b_iso88591_A_1D_wc_xuAV2_b_q_t1, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[3])) goto bad;
   }
   {
     const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 1, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 1};
     PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self};
-    __pyx_mstate_global->__pyx_codeobj_tab[3] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_stringsource, __pyx_mstate->__pyx_n_u_reduce_cython, __pyx_mstate->__pyx_kp_b_iso88591_Q, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[3])) goto bad;
+    __pyx_mstate_global->__pyx_codeobj_tab[4] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_stringsource, __pyx_mstate->__pyx_n_u_reduce_cython, __pyx_mstate->__pyx_kp_b_iso88591_Q, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[4])) goto bad;
   }
   {
     const __Pyx_PyCode_New_function_description descr = {2, 0, 0, 2, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 3};
     PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_pyx_state};
-    __pyx_mstate_global->__pyx_codeobj_tab[4] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_stringsource, __pyx_mstate->__pyx_n_u_setstate_cython, __pyx_mstate->__pyx_kp_b_iso88591_Q, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[4])) goto bad;
+    __pyx_mstate_global->__pyx_codeobj_tab[5] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_stringsource, __pyx_mstate->__pyx_n_u_setstate_cython, __pyx_mstate->__pyx_kp_b_iso88591_Q, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[5])) goto bad;
   }
   {
-    const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 4, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 459};
+    const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 4, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 470};
     PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_it, __pyx_mstate->__pyx_n_u_block, __pyx_mstate->__pyx_n_u_py_block};
-    __pyx_mstate_global->__pyx_codeobj_tab[5] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_print_key_value_pair, __pyx_mstate->__pyx_kp_b_iso88591_A_T_F_c_D_4q_c_L_1_iq, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[5])) goto bad;
+    __pyx_mstate_global->__pyx_codeobj_tab[6] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_print_key_value_pair, __pyx_mstate->__pyx_kp_b_iso88591_A_T_F_c_D_4q_c_L_1_iq, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[6])) goto bad;
   }
   {
-    const __Pyx_PyCode_New_function_description descr = {2, 0, 0, 7, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 469};
+    const __Pyx_PyCode_New_function_description descr = {2, 0, 0, 7, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 480};
     PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_max_num, __pyx_mstate->__pyx_n_u_block, __pyx_mstate->__pyx_n_u_max_nummber, __pyx_mstate->__pyx_n_u_idx, __pyx_mstate->__pyx_n_u_num, __pyx_mstate->__pyx_n_u_py_block};
-    __pyx_mstate_global->__pyx_codeobj_tab[6] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_print_blocks, __pyx_mstate->__pyx_kp_b_iso88591_A_a_1_83a_AQ_G5_WARuA_D_q_1_iq_1, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[6])) goto bad;
+    __pyx_mstate_global->__pyx_codeobj_tab[7] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_print_blocks, __pyx_mstate->__pyx_kp_b_iso88591_A_a_1_83a_AQ_G5_WARuA_D_q_1_iq_1, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[7])) goto bad;
   }
   {
-    const __Pyx_PyCode_New_function_description descr = {2, 0, 0, 3, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 486};
+    const __Pyx_PyCode_New_function_description descr = {2, 0, 0, 3, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 497};
     PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_idx, __pyx_mstate->__pyx_n_u_block};
-    __pyx_mstate_global->__pyx_codeobj_tab[7] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_get_block, __pyx_mstate->__pyx_kp_b_iso88591_A_4r_3d_D_AQ_D_AQ_6_A_AQ_iq_Q, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[7])) goto bad;
+    __pyx_mstate_global->__pyx_codeobj_tab[8] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_get_block, __pyx_mstate->__pyx_kp_b_iso88591_A_4r_3d_D_AQ_D_AQ_6_A_AQ_iq_Q, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[8])) goto bad;
   }
   {
-    const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 5, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 495};
+    const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 5, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 506};
     PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_genesis_prev_hash, __pyx_mstate->__pyx_n_u_data_str, __pyx_mstate->__pyx_n_u_block, __pyx_mstate->__pyx_n_u_res};
-    __pyx_mstate_global->__pyx_codeobj_tab[8] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_create_genesis_block, __pyx_mstate->__pyx_kp_b_iso88591_A_4q_a_YgQa_t_Qa_IQ_Q_gQa_t_Qa_4, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[8])) goto bad;
+    __pyx_mstate_global->__pyx_codeobj_tab[9] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_create_genesis_block, __pyx_mstate->__pyx_kp_b_iso88591_A_4q_a_YgQa_t_Qa_IQ_Q_gQa_t_Qa_4, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[9])) goto bad;
   }
   {
-    const __Pyx_PyCode_New_function_description descr = {2, 0, 0, 10, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 518};
+    const __Pyx_PyCode_New_function_description descr = {2, 0, 0, 10, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 529};
     PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_data, __pyx_mstate->__pyx_n_u_prev_block, __pyx_mstate->__pyx_n_u_prev_hash, __pyx_mstate->__pyx_n_u_new_idx, __pyx_mstate->__pyx_n_u_data_str, __pyx_mstate->__pyx_n_u_data_digest, __pyx_mstate->__pyx_n_u_digest_size, __pyx_mstate->__pyx_n_u_block, __pyx_mstate->__pyx_n_u_res};
-    __pyx_mstate_global->__pyx_codeobj_tab[9] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_new_block, __pyx_mstate->__pyx_kp_b_iso88591_A_4t1_aq_4z_1A_4z_T_Qd_Ja_hb_IQ, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[9])) goto bad;
+    __pyx_mstate_global->__pyx_codeobj_tab[10] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_new_block, __pyx_mstate->__pyx_kp_b_iso88591_A_4t1_aq_4z_1A_4z_T_Qd_Ja_hb_IQ, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[10])) goto bad;
   }
   {
-    const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 8, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 551};
+    const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 8, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 562};
     PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_block, __pyx_mstate->__pyx_n_u_prev_block, __pyx_mstate->__pyx_n_u_idx, __pyx_mstate->__pyx_n_u_digest, __pyx_mstate->__pyx_n_u_digest_size, __pyx_mstate->__pyx_n_u_py_bytes, __pyx_mstate->__pyx_n_u_py_bytes_rehashed};
-    __pyx_mstate_global->__pyx_codeobj_tab[10] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_validate, __pyx_mstate->__pyx_kp_b_iso88591_A_a_G5_WARuA_D_q_1_uHAU_waq_1G1A, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[10])) goto bad;
+    __pyx_mstate_global->__pyx_codeobj_tab[11] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_validate, __pyx_mstate->__pyx_kp_b_iso88591_A_a_G5_WARuA_D_q_1_uHAU_waq_1G1A, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[11])) goto bad;
   }
   {
-    const __Pyx_PyCode_New_function_description descr = {2, 0, 0, 7, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 579};
+    const __Pyx_PyCode_New_function_description descr = {2, 0, 0, 7, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 590};
     PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_min_idx, __pyx_mstate->__pyx_n_u_entries, __pyx_mstate->__pyx_n_u_block, __pyx_mstate->__pyx_n_u_idx, __pyx_mstate->__pyx_n_u_min_idx_2, __pyx_mstate->__pyx_n_u_contents};
-    __pyx_mstate_global->__pyx_codeobj_tab[11] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_get_saving_entries, __pyx_mstate->__pyx_kp_b_iso88591_A_a_83a_q_G5_WARuA_t3a_D_q_1_q_A, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[11])) goto bad;
+    __pyx_mstate_global->__pyx_codeobj_tab[12] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_get_saving_entries, __pyx_mstate->__pyx_kp_b_iso88591_A_a_83a_q_G5_WARuA_t3a_D_q_1_q_A, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[12])) goto bad;
   }
   {
-    const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 7, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 606};
+    const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 7, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 617};
     PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_stmt, __pyx_mstate->__pyx_n_u_conn, __pyx_mstate->__pyx_n_u_result, __pyx_mstate->__pyx_n_u_max_value, __pyx_mstate->__pyx_n_u_entries, __pyx_mstate->__pyx_n_u_con};
-    __pyx_mstate_global->__pyx_codeobj_tab[12] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_save, __pyx_mstate->__pyx_kp_b_iso88591_A_s_U_ar_q_T_gQ_4q_vQ_xq_7_2Zq, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[12])) goto bad;
+    __pyx_mstate_global->__pyx_codeobj_tab[13] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_save, __pyx_mstate->__pyx_kp_b_iso88591_A_s_U_ar_q_T_gQ_4q_vQ_xq_7_2Zq, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[13])) goto bad;
   }
   {
-    const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 1, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 621};
+    const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 1, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 632};
     PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self};
-    __pyx_mstate_global->__pyx_codeobj_tab[13] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_close_db_connections, __pyx_mstate->__pyx_kp_b_iso88591_A_HHA, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[13])) goto bad;
+    __pyx_mstate_global->__pyx_codeobj_tab[14] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_close_db_connections, __pyx_mstate->__pyx_kp_b_iso88591_A_HHA, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[14])) goto bad;
   }
   {
-    const __Pyx_PyCode_New_function_description descr = {2, 0, 0, 5, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 624};
+    const __Pyx_PyCode_New_function_description descr = {2, 0, 0, 5, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 635};
     PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_batch_size, __pyx_mstate->__pyx_n_u_con, __pyx_mstate->__pyx_n_u_res, __pyx_mstate->__pyx_n_u_batch};
-    __pyx_mstate_global->__pyx_codeobj_tab[14] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_load, __pyx_mstate->__pyx_kp_b_iso88591_A_4q_aq_q_XQc_89ARwb_dRS_IS_1A_K, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[14])) goto bad;
+    __pyx_mstate_global->__pyx_codeobj_tab[15] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_src_dopt_pollublock_blockchain_b, __pyx_mstate->__pyx_n_u_load, __pyx_mstate->__pyx_kp_b_iso88591_A_4q_aq_q_XQc_89ARwb_dRS_IS_1A_K, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[15])) goto bad;
   }
   {
     const __Pyx_PyCode_New_function_description descr = {1, 0, 0, 1, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 1};
     PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self};
-    __pyx_mstate_global->__pyx_codeobj_tab[15] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_stringsource, __pyx_mstate->__pyx_n_u_reduce_cython, __pyx_mstate->__pyx_kp_b_iso88591_Q, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[15])) goto bad;
+    __pyx_mstate_global->__pyx_codeobj_tab[16] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_stringsource, __pyx_mstate->__pyx_n_u_reduce_cython, __pyx_mstate->__pyx_kp_b_iso88591_Q, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[16])) goto bad;
   }
   {
     const __Pyx_PyCode_New_function_description descr = {2, 0, 0, 2, (unsigned int)(CO_OPTIMIZED|CO_NEWLOCALS), 3};
     PyObject* const varnames[] = {__pyx_mstate->__pyx_n_u_self, __pyx_mstate->__pyx_n_u_pyx_state};
-    __pyx_mstate_global->__pyx_codeobj_tab[16] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_stringsource, __pyx_mstate->__pyx_n_u_setstate_cython, __pyx_mstate->__pyx_kp_b_iso88591_Q, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[16])) goto bad;
+    __pyx_mstate_global->__pyx_codeobj_tab[17] = __Pyx_PyCode_New(descr, varnames, __pyx_mstate->__pyx_kp_u_stringsource, __pyx_mstate->__pyx_n_u_setstate_cython, __pyx_mstate->__pyx_kp_b_iso88591_Q, tuple_dedup_map); if (unlikely(!__pyx_mstate_global->__pyx_codeobj_tab[17])) goto bad;
   }
   Py_DECREF(tuple_dedup_map);
   return 0;
diff --git a/src/dopt_pollublock_blockchain/blockchain.pyi b/src/dopt_pollublock_blockchain/blockchain.pyi
index d4cc79a..3080b95 100644
--- a/src/dopt_pollublock_blockchain/blockchain.pyi
+++ b/src/dopt_pollublock_blockchain/blockchain.pyi
@@ -12,6 +12,7 @@ class PyBlock:
     def __init__(self) -> None: ...
     def __repr__(self) -> str: ...
     def __str__(self) -> str: ...
+    def as_dataclass(self) -> t.PyBlockData: ...
     def serialize_dict(self) -> t.SerializedPyBlock: ...
     @property
     def index(self) -> int: ...
diff --git a/src/dopt_pollublock_blockchain/blockchain.pyx b/src/dopt_pollublock_blockchain/blockchain.pyx
index f5886ea..4f5057b 100644
--- a/src/dopt_pollublock_blockchain/blockchain.pyx
+++ b/src/dopt_pollublock_blockchain/blockchain.pyx
@@ -11,6 +11,7 @@ import dopt_basics.datetime
 import sqlalchemy as sql
 from dopt_pollublock_blockchain import db
 
+from dopt_pollublock_blockchain import types
 
 from dopt_pollublock_blockchain.block cimport Block
 from libcpp.unordered_map cimport unordered_map
@@ -135,13 +136,23 @@ cdef class PyBlock:
 
     def __repr__(self):
         return (
-            f"PyBlock(\n\tIndex:\t\t{self.index}\n\ttimestamp:\t{self.timestamp}\n\tnonce:\t\t{self.nonce}\n\t"
+            f"PyBlock(\n\tIndex:\t\t{self.index}\n\tTimestamp:\t{self.timestamp}\n\tNonce:\t\t{self.nonce}\n\t"
             f"Prev Hash:\t{self.prev_hash}\n\tHash:\t\t{self.hash}\n\tData:\t\t{self.data}\n)"
         )
     
     def __str__(self):
         return self.__repr__()
 
+    def as_dataclass(self):
+        return types.PyBlockData(
+            Index=self.index,
+            Timestamp=self.timestamp,
+            Nonce=self.nonce,
+            PrevHash=self.prev_hash,
+            Hash=self.hash,
+            Data=self.data,
+        )
+
     def serialize_dict(self):
         contents = {}
 
diff --git a/src/dopt_pollublock_blockchain/constants.py b/src/dopt_pollublock_blockchain/constants.py
index 12c32bc..4a5a430 100644
--- a/src/dopt_pollublock_blockchain/constants.py
+++ b/src/dopt_pollublock_blockchain/constants.py
@@ -1,5 +1,19 @@
 from __future__ import annotations
 
+import random
 from typing import Final
 
+# ** blockchain
+BLOCKCHAIN_LOADING_BATCH_SIZE: Final[int] = 256
 BLOCKCHAIN_DIFFICULTY: Final[int] = 24
+
+# ** data sampling
+RNG_SEED_RANGE: Final[frozenset[str]] = frozenset(str(seed) for seed in range(1, 101))
+RNG_DEFAULT_SEED: Final[int | None] = 42
+RNG: Final[random.Random] = random.Random(RNG_DEFAULT_SEED)
+TEMPERATURE_MEAN: Final[float] = 344.224456
+TEMPERATURE_STD: Final[float] = 46.478794
+PRESSURE_MIN: Final[int] = 15587
+PRESSURE_MAX: Final[int] = 15602
+AIRQTY_MEAN: Final[float] = -22.958655
+AIRQTY_STD: Final[float] = 2.101152
diff --git a/src/dopt_pollublock_blockchain/types.py b/src/dopt_pollublock_blockchain/types.py
index 1633b2c..3b668bd 100644
--- a/src/dopt_pollublock_blockchain/types.py
+++ b/src/dopt_pollublock_blockchain/types.py
@@ -1,8 +1,28 @@
+from __future__ import annotations
+
+import dataclasses as dc
+import datetime
+import enum
 from typing import TypeAlias, TypedDict
 
 BlockIndex: TypeAlias = int
 
 
+class ApplicationScenarios(enum.IntEnum):
+    DATA_VALIDATION = 1
+    DATA_GENERATION = 2
+
+
+@dc.dataclass(slots=True, kw_only=True, eq=False)
+class PyBlockData:
+    Index: int
+    Timestamp: datetime.datetime
+    Nonce: int
+    PrevHash: str
+    Hash: str
+    Data: str
+
+
 class SerializedPyBlock(TypedDict):
     index: int
     timestamp: int
@@ -10,3 +30,15 @@ class SerializedPyBlock(TypedDict):
     previous_hash: str
     hash: str
     data: str
+
+
+RandomSampleEntry = TypedDict(
+    "RandomSampleEntry",
+    {
+        "Datetime": datetime.datetime,
+        "Temperature_(Celsius)": float,
+        "Pressure_(Pa)": int,
+        "Air_Quantity_(Percent)": float,
+        "Blockchain_Block_Number": int | None,
+    },
+)