public function upgrade_confirm_page($strnewversion, $maturity, $testsite) {
        $output = '';

        $continueurl = new moodle_url($this->page->url, array('confirmupgrade' => 1, 'cache' => 0));
        $continue = new single_button($continueurl, get_string('continue'), 'get');
        $cancelurl = new moodle_url('/admin/index.php');

        $output .= $this->header();
        $output .= $this->maturity_warning($maturity);
        $output .= $this->test_site_warning($testsite);
        $output .= $this->confirm(get_string('upgradesure', 'admin', $strnewversion), $continue, $cancelurl);
        $output .= $this->footer();

        return $output;
    }