def set_by_cli(var):
    detector = set_by_cli.detector
    if detector is None:
        # Setup on first run: `detector` is a weird version of config in which
        # the default value of every attribute is wrangled to be boolean-false
        plugins = plugins_disco.PluginsRegistry.find_all()
        # reconstructed_args == sys.argv[1:], or whatever was passed to main()
        reconstructed_args = helpful_parser.args + [helpful_parser.verb]
        detector = set_by_cli.detector = prepare_and_parse_args(
            plugins, reconstructed_args, detect_defaults=True)
        # propagate plugin requests: eg --standalone modifies config.authenticator
        detector.authenticator, detector.installer = (
            plugin_selection.cli_plugin_requests(detector))
        logger.debug("Default Detector is %r", detector)

    if not isinstance(getattr(detector, var), _Default):
        return True

    for modifier in VAR_MODIFIERS.get(var, []):
        if set_by_cli(modifier):
            return True

    return False
# static housekeeping var
Return True if a particular config variable has been set by the user
dataset/ETHPy150Open letsencrypt/letsencrypt/certbot/cli.py/set_by_cli