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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 check(self, results_id):
 """Check for results of a membership request. :param str results_id: the ID of a membership request :return: successfully created memberships :rtype: :class:`list` :raises groupy.exceptions.ResultsNotReady: if the results are not ready :raises groupy.exceptions.ResultsExpired: if the results have expired """

        path = 'results/{}'.format(results_id)
        url = utils.urljoin(self.url, path)
        response = self.session.get(url)
        if response.status_code == 503:
            raise exceptions.ResultsNotReady(response)
        if response.status_code == 404:
            raise exceptions.ResultsExpired(response)
        return response.data['members']