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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 by_summoner(self, region, encrypted_summoner_id):
 """ FOR KR SUMMONERS, A 404 WILL ALWAYS BE RETURNED. Valid codes must be no longer than 256 characters and only use valid characters: 0-9, a-z, A-Z, and - :param string region: the region to execute this request on :param string encrypted_summoner_id: Summoner ID :returns: string """

        url, query = ThirdPartyCodeApiV4Urls.by_summoner(
            region=region, encrypted_summoner_id=encrypted_summoner_id
        )

        return self._raw_request(self.by_summoner.__name__, region, url, query)