public static function print_expired_export() {
        global $CFG, $OUTPUT, $PAGE;
        $title = get_string('exportexpired', 'portfolio');
        $PAGE->navbar->add(get_string('exportexpired', 'portfolio'));
        $PAGE->set_title($title);
        $PAGE->set_heading($title);
        echo $OUTPUT->header();
        echo $OUTPUT->notification(get_string('exportexpireddesc', 'portfolio'));
        echo $OUTPUT->continue_button($CFG->wwwroot);
        echo $OUTPUT->footer();
        exit;
    }