public static function print_cleaned_export($log, $instance=null) {
        global $CFG, $OUTPUT, $PAGE;
        if (empty($instance) || !$instance instanceof portfolio_plugin_base) {
            $instance = portfolio_instance($log->portfolio);
        }
        $title = get_string('exportalreadyfinished', 'portfolio');
        $PAGE->navbar->add($title);
        $PAGE->set_title($title);
        $PAGE->set_heading($title);
        echo $OUTPUT->header();
        echo $OUTPUT->notification(get_string('exportalreadyfinished', 'portfolio'));
        self::print_finish_info($log->returnurl, $instance->resolve_static_continue_url($log->continueurl));
        echo $OUTPUT->continue_button($CFG->wwwroot);
        echo $OUTPUT->footer();
        exit;
    }