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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 expectAck(self):
 """ When the most recent packet produced as an output of this state machine is acknowledged by our peer, generate a single 'ack' input. """

        last = self.lastTransmitted
        self.ackPredicate = lambda ackPacket: (
            ackPacket.relativeAck() >= last.relativeSeq()
        )