@Override
  public @NotNull String getXmlElementNamespace() {
    final DomInvocationHandler parent = getParentHandler();
    assert parent != null : "this operation should be performed on the DOM having a physical parent, your DOM may be not very fresh";
    final XmlElement element = parent.getXmlElement();
    assert element != null;
    return getXmlName().getNamespace(element, getFile());
  }
@Override
  public @NotNull String getXmlElementNamespace()