public static function add_disabled_constraints_to_form(\MoodleQuickForm $mform) {
        $myvalue = \tool_usertours\target::get_target_constant_for_class(get_class());

        foreach (array_keys(self::$forcedsettings) as $settingname) {
            $mform->hideIf($settingname, 'targettype', 'eq', $myvalue);
        }
    }