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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:
 async def append(self, reply: Reply) \ -> None: """ Add the given Reply to this transaction store's list of responses. Also add to processedRequests if not added previously. """

        result = reply.result
        identifier = result.get(f.IDENTIFIER.nm)
        txnId = result.get(TXN_ID)
        logger.debug("Reply being sent {}".format(reply))
        if self._isNewTxn(identifier, reply, txnId):
            self.addToProcessedTxns(identifier, txnId, reply)
        if identifier not in self.responses:
            self.responses[identifier] = asyncio.Queue()
        await self.responses[identifier].put(reply)