code: def build_command(self):
          
          return cron_utils.cronify("crontab -l | {{ cat; echo \"{} {} {} {} {} CJOBID='{}' MAILTO='' {}\"; }} | crontab - > /dev/null".format(self._minute, self._hour, self._day_of_month, self._month_of_year, self._day_of_week, self._jobid, self._command))
docs: Build out the crontab command