code: def add_from_xmlnode(self, element):
          
          if self.tree is None:
              root = ET.Element('interface')
              root.append(element)
              self.tree = tree = ET.ElementTree(root)
              self.root = tree.getroot()
              self.objects = {}
              # ET.dump(tree)
          else:
              # TODO: append to current tree
              pass
docs: Load ui definition from xml.etree.Element node.