[pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Author: pre-commit-ci[bot]

blockchain/PoWAlgorithm.py

@@ -22,6 +22,7 @@
 import hashlib
 import time
 
+
 class Block:
     def __init__(self, index, previous_hash, transactions, timestamp, difficulty):
         self.index = index
@@ -35,7 +36,7 @@ def __init__(self, index, previous_hash, transactions, timestamp, difficulty):
     def compute_hash(self):
         """
         Generates the hash of the block content.
-        Combines index, previous hash, transactions, timestamp, and nonce into a string, 
+        Combines index, previous hash, transactions, timestamp, and nonce into a string,
         which is then hashed using SHA-256.
         """
         block_string = f"{self.index}{self.previous_hash}{self.transactions}{self.timestamp}{self.nonce}"
@@ -46,13 +47,16 @@ def mine_block(self):
         Performs Proof of Work by adjusting the nonce until a valid hash is found.
         A valid hash has the required number of leading zeros based on the difficulty level.
         """
-        target = '0' * self.difficulty  # Target hash should start with 'difficulty' number of zeros
-        while self.hash[:self.difficulty] != target:
+        target = (
+            "0" * self.difficulty
+        )  # Target hash should start with 'difficulty' number of zeros
+        while self.hash[: self.difficulty] != target:
             self.nonce += 1
             self.hash = self.compute_hash()
 
         print(f"Block mined with nonce {self.nonce}, hash: {self.hash}")
 
+
 class Blockchain:
     def __init__(self, difficulty):
         self.chain = []
@@ -72,13 +76,19 @@ def add_block(self, transactions):
         Adds a new block to the blockchain after performing Proof of Work.
         """
         previous_block = self.chain[-1]
-        new_block = Block(len(self.chain), previous_block.hash, transactions, time.time(), self.difficulty)
+        new_block = Block(
+            len(self.chain),
+            previous_block.hash,
+            transactions,
+            time.time(),
+            self.difficulty,
+        )
         new_block.mine_block()
         self.chain.append(new_block)
 
     def is_chain_valid(self):
         """
-        Verifies the integrity of the blockchain by ensuring each block's previous hash matches 
+        Verifies the integrity of the blockchain by ensuring each block's previous hash matches
         and that all blocks meet the Proof of Work requirement.
         """
         for i in range(1, len(self.chain)):
@@ -95,8 +105,10 @@ def is_chain_valid(self):
 
         return True
 
+
 # Test cases
 
+
 def test_blockchain():
     """
     Test cases for the Blockchain proof of work algorithm.
@@ -112,11 +124,16 @@ def test_blockchain():
     assert blockchain.is_chain_valid() == True, "Blockchain should be valid"
 
     # Tamper with the blockchain and check validation
-    blockchain.chain[1].transactions = "Transaction 1: Alice pays Bob 50 BTC"  # Tampering the transaction
-    assert blockchain.is_chain_valid() == False, "Blockchain should be invalid due to tampering"
+    blockchain.chain[
+        1
+    ].transactions = "Transaction 1: Alice pays Bob 50 BTC"  # Tampering the transaction
+    assert (
+        blockchain.is_chain_valid() == False
+    ), "Blockchain should be invalid due to tampering"
 
     print("All test cases passed.")
 
+
 if __name__ == "__main__":
     test_blockchain()