public static function course_updated(\core\event\course_updated $event) {
        if (class_exists('format_weeks', false)) {
            // If class format_weeks was never loaded, this is definitely not a course in 'weeks' format.
            // Course may still be in another format but format_weeks::update_end_date() will check it.
            format_weeks::update_end_date($event->courseid);
        }
    }