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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 get_batch_result_ids(self, job_id, batch_id):
 """ Get result IDs of a batch that has completed processing. """

        response = requests.get(self._get_batch_results_url(job_id, batch_id),
                                headers=self._get_batch_info_headers())
        response.raise_for_status()

        root = ET.fromstring(response.text)
        result_ids = [r.text for r in root.findall('%sresult' % self.API_NS)]

        return result_ids