<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _isNewTxn(self, identifier, reply, txnId) -> bool: """ If client is not in `processedRequests` or requestId is not there in processed requests and txnId is present then its a new reply """

        return (identifier not in self.processedRequests or
                reply.reqId not in self.processedRequests[identifier]) and \
            txnId is not None