def root(self):
        """
        TODO(rdelinger) rename this as to_xml or something similar
        """
        self.xml_root = ElementTree.Element('interface')
        self.xml_root.set('type', self.type)
        if self.mac is not None:
            mac = ElementTree.SubElement(self.xml_root, 'mac')
            mac.set('address', self.mac)
        _source = ElementTree.SubElement(self.xml_root, 'source')
        _source.set(self.type, self.source)
        _model = ElementTree.SubElement(self.xml_root, 'model')
        _model.set('type', self.model)
        return self.xml_root