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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 generate_replies(self, max_length, state_size, reply_to, dataset):
 """Generate replies. Parameters max_length : `int` or `None` Maximum sentence length. state_size : `int` State size. reply_to : `str` Input string. dataset: `str` Dataset key prefix. Returns ------- `generator` of `str` Generated texts. """

        state_sets = self.get_reply_states(
            reply_to,
            dataset + state_size_dataset(state_size)
        )

        if not state_sets:
            yield from self.generate_cont(max_length, state_size,
                                          None, False, dataset)
            return

        random.shuffle(state_sets)

        generate = lambda state, backward: self.generate(
            state_size, state,
            dataset, backward
        )

        for states in cycle(state_sets):
            state = random.choice(states)
            parts = chain(
                reversed(list(generate(state, True))),
                (state,),
                generate(state, False)
            )
            parts = islice(parts, 0, max_length)
            yield self.format(parts)