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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 _update_job_info(cls, job_dir):
 """Update information for given job. Meta file will be loaded if exists, and the job information in in db backend will be updated. Args: job_dir (str):
 Directory path of the job. Return: Updated dict of job meta info """

        meta_file = os.path.join(job_dir, JOB_META_FILE)
        meta = parse_json(meta_file)

        if meta:
            logging.debug("Update job info for %s" % meta["job_id"])
            JobRecord.objects \
                .filter(job_id=meta["job_id"]) \
                .update(end_time=timestamp2date(meta["end_time"]))