public function course_context_id()
 {
     if ((int) $this->record->contextlevel === CONTEXT_COURSE) {
         return $this->record->id;
     } else {
         return parent::course_context_id();
     }
 }
 protected function children(qtype_ddmarker_list_item $item)
 {
     $children = array();
     foreach ($item->get_children() as $child) {
         $children[] = $this->render_qtype_ddmarker_list_item($child);
     }
     return html_writer::alist($children);
 }