code: def is_deposit_confirmed(
          channel_state: NettingChannelState,
          block_number: BlockNumber,
  ) -> bool:
      
      if not channel_state.deposit_transaction_queue:
          return False
  
      return is_transaction_confirmed(
          channel_state.deposit_transaction_queue[0].block_number,
          block_number,
      )
docs: True if the block which mined the deposit transaction has been
      confirmed.