public function get_collectionlabel() {
        if (!empty($this->collectionlabel)) {
            return $this->collectionlabel;
        }
        if ($this->parent && ($this->parent instanceof flat_navigation_node || $this->parent instanceof flat_navigation)) {
            return $this->parent->get_collectionlabel();
        }
        debugging('Navigation region requires a label', DEBUG_DEVELOPER);
        return '';
    }