code: def AddTransaction(self, tx):
          
          if BC.Default() is None:
              return False
  
          if tx.Hash.ToBytes() in self.MemPool.keys():
              return False
  
          if BC.Default().ContainsTransaction(tx.Hash):
              return False
  
          if not tx.Verify(self.MemPool.values()):
              logger.error("Verifying tx result... failed")
              return False
  
          self.MemPool[tx.Hash.ToBytes()] = tx
  
          return True
docs: Add a transaction to the memory pool.
  
          Args:
              tx (neo.Core.TX.Transaction): instance.
  
          Returns:
              bool: True if successfully added. False otherwise.