input: def create_blockchain():
      """
      Create a blockchain system in Python with each block containing an index, timestamp, data, and previous hash.
      The blockchain starts with a genesis block and then adds subsequent blocks based on provided transactions.
      Example:
      >>> create_blockchain()
      [Block(0, '2023-01-01 12:00:00', 'Genesis Block', '0'), Block(1, '2023-01-02 12:00:00', 'Transaction 1', 'hash1'), Block(2, '2023-01-03 12:00:00', 'Transaction 2', 'hash2')]
      """
output:     from dataclasses import dataclass
      from datetime import datetime
      import hashlib
  
      @dataclass
      class Block:
          index: int
          timestamp: str
          data: str
          previous_hash: str
  
          def compute_hash(self):
              block_string = f"{self.index}{self.timestamp}{self.data}{self.previous_hash}"
              return hashlib.sha256(block_string.encode()).hexdigest()
  
      def create_blockchain():
          blockchain = []
          genesis_block = Block(0, datetime.now().strftime('%Y-%m-%d %H:%M:%S'), 'Genesis Block', '0')
          blockchain.append(genesis_block)
  
          transactions = ['Transaction 1', 'Transaction 2']
          for i, transaction in enumerate(transactions, start=1):
              previous_block = blockchain[-1]
              new_block = Block(i, datetime.now().strftime('%Y-%m-%d %H:%M:%S'), transaction, previous_block.compute_hash())
              blockchain.append(new_block)
  
          return blockchain