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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_query_schema(self, job_id):
 """Retrieve the schema of a query by job id. Parameters job_id : str The job_id that references a BigQuery query Returns ------- list A ``list`` of ``dict`` objects that represent the schema. """


        query_reply = self.get_query_results(job_id, offset=0, limit=0)

        if not query_reply['jobComplete']:
            logger.warning('BigQuery job %s not complete' % job_id)
            raise UnfinishedQueryException()

        return query_reply['schema']['fields']