public static function get_subwikis_returns() {
        return new external_single_structure(
            array(
                'subwikis' => new external_multiple_structure(
                    new external_single_structure(
                        array(
                            'id' => new external_value(PARAM_INT, 'Subwiki ID.'),
                            'wikiid' => new external_value(PARAM_INT, 'Wiki ID.'),
                            'groupid' => new external_value(PARAM_RAW, 'Group ID.'),
                            'userid' => new external_value(PARAM_INT, 'User ID.'),
                            'canedit' => new external_value(PARAM_BOOL, 'True if user can edit the subwiki.'),
                        ), 'Subwikis'
                    )
                ),
                'warnings' => new external_warnings(),
            )
        );
    }