docs: def enable_logging(log_level):
      # type: (typing.Union[None, int]) -> None
      """Configure the root logger and a logfile handler.
  
      Args:
          log_level: The logging level to set the logger handler.
      """
      root_logger = logging.getLogger()
      root_logger.setLevel(logging.DEBUG)
      logfile_handler = logging.StreamHandler(_LOGFILE_STREAM)
      logfile_handler.setLevel(logging.DEBUG)
      logfile_handler.setFormatter(logging.Formatter(
          '%(levelname)s [%(asctime)s][%(name)s] %(message)s'))
      root_logger.addHandler(logfile_handler)
      if signal.getsignal(signal.SIGTERM) == signal.SIG_DFL:
          signal.signal(signal.SIGTERM, _logfile_sigterm_handler)
      if log_level:
          handler = logging.StreamHandler()
          handler.setFormatter(_LogColorFormatter())
          root_logger.setLevel(log_level)
          root_logger.addHandler(handler)