docs: def WriteCronJob(self, cronjob, cursor=None):
      """Writes a cronjob to the database."""
      query = ("INSERT INTO cron_jobs "
               "(job_id, job, create_time, enabled) "
               "VALUES (%s, %s, FROM_UNIXTIME(%s), %s) "
               "ON DUPLICATE KEY UPDATE "
               "enabled=VALUES(enabled)")
  
      create_time_str = mysql_utils.RDFDatetimeToTimestamp(
          cronjob.created_at or rdfvalue.RDFDatetime.Now())
      cursor.execute(query, [
          cronjob.cron_job_id,
          cronjob.SerializeToString(), create_time_str, cronjob.enabled
      ])