@Override
  public void writeExternal(Element element) throws WriteExternalException {
    super.writeExternal(element);
    if (myLabelRenderer != null) {
      final Element labelRendererElement = myRendererSettings.writeRenderer(myLabelRenderer);
      labelRendererElement.setAttribute("role", "label");
      element.addContent(labelRendererElement);
    }
    if (myChildrenRenderer != null) {
      final Element childrenRendererElement = myRendererSettings.writeRenderer(myChildrenRenderer);
      childrenRendererElement.setAttribute("role", "children");
      element.addContent(childrenRendererElement);
    }
  }
@Override
  public void writeExternal(Element element)