def parse_response(response, return_type):
        '''
        Parse the HTTPResponse's body and fill all the data into a class of
        return_type.
        '''
        root = ETree.fromstring(response.body)
        xml_name = getattr(return_type, '_xml_name', return_type.__name__)
        if root.tag == xml_name:
            return _ETreeXmlToObject._parse_response_body_from_xml_node(root, return_type)

        return None
Parse the HTTPResponse's body and fill all the data into a class of
        return_type.