code: def encode(self):
          
          root_element = ElementTree.Element(self.TAG_NAME)
          for value in [value for value in self.__dict__.values() if isinstance(value, fields.Field)]:
              if value.required or value.value:
                  root_element.append(value.encode())
          return root_element
docs: Encodes the object to a xml.etree.ElementTree.Element
  
          :return: the encoded element
          :rtype: xml.etree.ElementTree.Element