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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def RemoveTransaction(self, tx):
 """ Remove a transaction from the memory pool if it is found on the blockchain. Args: tx (neo.Core.TX.Transaction):
 instance. Returns: bool: True if successfully removed. False otherwise. """

        if BC.Default() is None:
            return False

        if not BC.Default().ContainsTransaction(tx.Hash):
            return False

        if tx.Hash.ToBytes() in self.MemPool:
            del self.MemPool[tx.Hash.ToBytes()]
            return True

        return False