input: 
  def create_blockchain(blockchain_transactions):
      """Create a simple blockchain system based on a list of transactions.
      The function should generate blocks from transactions, starting with a genesis block.
      
      >>> create_blockchain([{'data': 'First block'}])
      [Block(index=0, timestamp='2023-10-01 12:00:00', data={'data': 'First block'}, previous_hash='0')]
      >>> create_blockchain([{'data': 'First block'}, {'data': 'Second block'}])
      [Block(index=0, timestamp='2023-10-01 12:00:00', data={'data': 'First block'}, previous_hash='0'),
       Block(index=1, timestamp='2023-10-01 12:00:01', data={'data': 'Second block'}, previous_hash='hash of first block')]
      """
  
output:     from collections import namedtuple
      import time
  
      Block = namedtuple('Block', ['index', 'timestamp', 'data', 'previous_hash'])
  
      def calculate_hash(block):
          return str(block.index) + str(block.timestamp) + str(block.data) + str(block.previous_hash)
  
      blockchain = []
      genesis_block = Block(index=0, timestamp='2023-10-01 12:00:00', data={'data': 'First block'}, previous_hash='0')
      blockchain.append(genesis_block)
  
      for i, transaction in enumerate(blockchain_transactions[1:], start=1):
          previous_block = blockchain[-1]
          new_block = Block(index=i, timestamp='2023-10-01 12:00:0' + str(i), data=transaction, previous_hash=calculate_hash(previous_block))
          blockchain.append(new_block)
  
      return blockchain