code: def fromXml(cls, elem):
          
          if elem is None:
              return None
  
          addon = cls.byName(elem.tag)
          if not addon:
              raise RuntimeError('{0} is not a supported XML tag'.format(elem.tag))
  
          return addon.load(elem)
docs: Converts the inputted element to a Python object by looking through
          the IO addons for the element's tag.
          
          :param      elem | <xml.etree.ElementTree.Element>
          
          :return     <variant>