def METHOD_NAME(self):
    if any((self.args.name, self.args.value, self.args.unset)):
        logger.error(
            "-l/--list can't be used together with any of these "
            "options: -u/--unset, name, value"
        )
        return 1
    levels = self._get_appropriate_levels(self.args.level)
    for level in levels:
        conf = self.config.read(level)
        prefix = self._config_file_prefix(self.args.show_origin, self.config, level)
        configs = list(self._format_config(conf, prefix))
        if configs:
            ui.write("\n".join(configs))
    return 0