<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def encode(self):
 """ Encodes the object to a xml.etree.ElementTree.Element :return: the encoded element :rtype: xml.etree.ElementTree.Element """

        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