Update proof_of_work.py

Author: divyaSree-S0

blockchain/proof_of_work.py

@@ -1,12 +1,11 @@
 import hashlib
-import time
 
 
 def proof_of_work(difficulty: int) -> int:
     """
     Simulates a Proof of Work mining process.
 
-    The miner must find a nonce such that the hash of the nonce starts
+    The miner must find a nonce such that the hash of the nonce starts 
     with a specific number of leading zeros (difficulty).
 
     Args:
@@ -20,13 +19,11 @@ def proof_of_work(difficulty: int) -> int:
         >>> isinstance(result, int)
         True
     """
-    prefix = "0" * difficulty
+    prefix = '0' * difficulty
     nonce = 0
-    start = time.time()  # Timing starts
 
     while True:
         hash_result = hashlib.sha256(f"{nonce}".encode()).hexdigest()
         if hash_result.startswith(prefix):
-            end = time.time()  # Timing ends
             return nonce
         nonce += 1