diff --git a/2_bitcoin_mining/bitcoin_mining.py b/2_bitcoin_mining/bitcoin_mining.py
index f2a20c1..e2b41f9 100644
--- a/2_bitcoin_mining/bitcoin_mining.py
+++ b/2_bitcoin_mining/bitcoin_mining.py
@@ -1,11 +1,14 @@
 from hashlib import sha256
+
 MAX_NONCE = 100000000000
 
+
 def SHA256(text):
     return sha256(text.encode("ascii")).hexdigest()
 
+
 def mine(block_number, transactions, previous_hash, prefix_zeros):
-    prefix_str = '0'*prefix_zeros
+    prefix_str = "0" * prefix_zeros
     for nonce in range(MAX_NONCE):
         text = str(block_number) + transactions + previous_hash + str(nonce)
         new_hash = SHA256(text)
@@ -15,16 +18,23 @@ def mine(block_number, transactions, previous_hash, prefix_zeros):
 
     raise BaseException(f"Couldn't find correct has after trying {MAX_NONCE} times")
 
-if __name__=='__main__':
-    transactions='''
+
+if __name__ == "__main__":
+    transactions = """
     Dhaval->Bhavin->20,
     Mando->Cara->45
-    '''
-    difficulty=4 # try changing this to higher number and you will see it will take more time for mining as difficulty increases
+    """
+    difficulty = 4  # try changing this to higher number and you will see it will take more time for mining as difficulty increases
     import time
+
     start = time.time()
     print("start mining")
-    new_hash = mine(5,transactions,'0000000xa036944e29568d0cff17edbe038f81208fecf9a66be9a2b8321c6ec7', difficulty)
+    new_hash = mine(
+        5,
+        transactions,
+        "0000000xa036944e29568d0cff17edbe038f81208fecf9a66be9a2b8321c6ec7",
+        difficulty,
+    )
     total_time = str((time.time() - start))
     print(f"end mining. Mining took: {total_time} seconds")
-    print(new_hash)
\ No newline at end of file
+    print(new_hash)