1+ from hashlib import sha256
2+ MAX_NONCE = 100000000000
3+
4+ def SHA256 (text ):
5+ return sha256 (text .encode ("ascii" )).hexdigest ()
6+
7+ def mine (block_number ,transactions ,previous_hash ,prefix_zeros ):
8+ prefix_str = '0' * prefix_zeros
9+ for nonce in range (MAX_NONCE ):
10+ text = str (block_number )+ transactions + previous_hash + str (nonce )
11+ new_hash = SHA256 (text )
12+ if new_hash .startswith (prefix_str ):
13+ print (f"Yay! Successfully mined bitcoins with nonce value:{ nonce } )
14+ return new_hash
15+
16+ raise BaseException (f"Couldn't find correct has after trying{ MAX_NONCE } )
17+
18+ if __name__ == '__main__' :
19+ transactions = '''
20+ Dhaval->Bhavin->20,
21+ Mando->Cara->45
22+ '''
23+ difficulty = 4 # try changing this to higher number and you will see it will take more time for mining as difficulty increases
24+ import time
25+ start = time .time ()
26+ print ("start mining" )
27+ new_hash = mine (5 ,transactions ,'0000000xa036944e29568d0cff17edbe038f81208fecf9a66be9a2b8321c6ec7' ,difficulty )
28+ total_time = str ((time .time ()- start ))
29+ print (f"end mining. Mining took:{ total_time } )
30+ print (new_hash )