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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 challenger_by_queue(self, region, queue):
 """ Get the challenger league for a given queue. :param string region: the region to execute this request on :param string queue: the queue to get the challenger players for :returns: LeagueListDTO """

        url, query = LeagueApiV4Urls.challenger_by_queue(region=region, queue=queue)
        return self._raw_request(self.challenger_by_queue.__name__, region, url, query)