How to use the geventhttpclient._parser.HTTPParseError function in geventhttpclient

HEADER_STATE_VALUE = 2
HEADER_STATE_DONE = 3


def copy(data):
    if six.PY3:
        return data[:]
    else:
        return str(data)


class HTTPConnectionClosed(HTTPParseError):
    pass


class HTTPProtocolViolationError(HTTPParseError):
    pass


class HTTPResponse(HTTPResponseParser):

    def __init__(self, method='GET', headers_type=Headers):
        super(HTTPResponse, self).__init__()
        self.method = method.upper()
        self.headers_complete = False
        self.message_begun = False
        self.message_complete = False
        self._headers_index = headers_type()
        self._header_state = HEADER_STATE_INIT
        self._current_header_field = None
        self._current_header_value = None
        self._header_position = 1

def _read_headers(self):
        try:
            start = True
            while not self.headers_complete:
                try:
                    data = self._sock.recv(self.block_size)
                    self.feed(data)
                    # depending on gevent version we get a conn reset or no data
                    if not len(data) and not self.headers_complete:
                        if start:
                            raise HTTPConnectionClosed(
                                'connection closed.')
                        raise HTTPParseError('connection closed before'
                                            ' end of the headers')
                    start = False
                except gevent.socket.error as e:
                    if e.errno == errno.ECONNRESET:
                        if start:
                            raise HTTPConnectionClosed(
                                'connection closed.')
                    raise

            if self.message_complete:
                self.release()
        except BaseException:
            self.release()
            raise

HEADER_STATE_INIT = 0
HEADER_STATE_FIELD = 1
HEADER_STATE_VALUE = 2
HEADER_STATE_DONE = 3


def copy(data):
    if six.PY3:
        return data[:]
    else:
        return str(data)


class HTTPConnectionClosed(HTTPParseError):
    pass


class HTTPProtocolViolationError(HTTPParseError):
    pass


class HTTPResponse(HTTPResponseParser):

    def __init__(self, method='GET', headers_type=Headers):
        super(HTTPResponse, self).__init__()
        self.method = method.upper()
        self.headers_complete = False
        self.message_begun = False
        self.message_complete = False
        self._headers_index = headers_type()