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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_update(self, id, title):
 """ Update info about a list, where "info" is really the lists `title`. Returns the `list dict`_ of the modified list. """

        id = self.__unpack_id(id)
        params = self.__generate_params(locals(), ['id'])
        return self.__api_request('PUT', '/api/v1/lists/{0}'.format(id), params)