Building a Basic Blockchain in Python: My Journey and Key Takeaways!

    def new_block(self, proof, previous_hash=None):

        block = {

            'index': len(self.chain) + 1,

            'timestamp': time(),

            'transactions': self.current_transactions,

            'proof': proof,

            'previous_hash': previous_hash or self.hash(self.chain[-1] if self.chain else '0'),

        }

    def new_transaction(self, sender, recipient, amount):

        # Add a new transaction to the list of transactions

        self.current_transactions.append({

            'sender': sender,

            'recipient': recipient,

            'amount': amount,

        })

        return self.last_block['index'] + 1  # Return the index of the block that will hold this transaction

 @staticmethod

    def hash(block):

        # Creates a SHA-256 hash of a Block

        block_string = json.dumps(block, sort_keys=True).encode()

        return hashlib.sha256(block_string).hexdigest()

def proof_of_work(self, last_proof):

        proof = 0

        while self.valid_proof(last_proof, proof) is False:

            proof += 1

        return proof



    @staticmethod 



def valid_proof(last_proof, proof):

        # Validates the Proof by checking if hash(last_proof, proof) has 4 leading zeroes

        guess = f"{last_proof}{proof}".encode()

        guess_hash = hashlib.sha256(guess).hexdigest()

        return guess_hash[:4] == "0000"