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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 _maybe_finish_job(self, job_id):
 """Returns True if job is finished."""

        job = brozzler.Job.load(self.rr, job_id)
        if not job:
            return False
        if job.status.startswith("FINISH"):
            self.logger.warn("%s is already %s", job, job.status)
            return True

        results = self.rr.table("sites").get_all(job_id, index="job_id").run()
        n = 0
        for result in results:
            site = brozzler.Site(self.rr, result)
            if not site.status.startswith("FINISH"):
                results.close()
                return False
            n += 1

        self.logger.info(
                "all %s sites finished, job %s is FINISHED!", n, job.id)
        job.finish()
        job.save()
        return True