private function helper_render_feedback($feedback) {

        $o  = '';    // output HTML code
        $o .= $this->output->container_start('feedback feedbackforauthor');
        $o .= $this->output->container_start('header');
        $o .= $this->output->heading(get_string('feedbackby', 'workshop', s(fullname($feedback->get_provider()))), 3, 'title');

        $userpic = $this->output->user_picture($feedback->get_provider(), array('courseid' => $this->page->course->id, 'size' => 32));
        $o .= $this->output->container($userpic, 'picture');
        $o .= $this->output->container_end(); // end of header

        $content = format_text($feedback->get_content(), $feedback->get_format(), array('overflowdiv' => true));
        $o .= $this->output->container($content, 'content');

        $o .= $this->output->container_end();

        return $o;
    }