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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 list_subscribers(self, list_id):
 """ List subscribers of a list :param list_id: list ID number :return: :class:`~responsebot.models.User` object """

        return [User(user._json) for user in self._client.list_subscribers(list_id=list_id)]