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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 getFactory(self):
 """ Return a server factory which creates AMP protocol instances. """

        factory = ServerFactory()
        def protocol():
            proto = CredReceiver()
            proto.portal = Portal(
                self.loginSystem,
                [self.loginSystem,
                 OneTimePadChecker(self._oneTimePads)])
            return proto
        factory.protocol = protocol
        return factory