def __send_message(self, msg):
        client = self.__collection.database.connection
        try:
            res = client._send_message_with_response(
                msg, _connection_to_use=self.__conn_id)
            self.__conn_id, (response, dummy0, dummy1) = res
        except AutoReconnect:
            # Don't try to send kill cursors on another socket
            # or to another server. It can cause a _pinValue
            # assertion on some server releases if we get here
            # due to a socket timeout.
            self.__killed = True
            raise

        try:
            response = helpers._unpack_response(response,
                                                self.__id,
                                                *self.__decode_opts)
        except CursorNotFound:
            self.__killed = True
            raise
        except AutoReconnect:
            # Don't send kill cursors to another server after a "not master"
            # error. It's completely pointless.
            self.__killed = True
            client.disconnect()
            raise
        self.__id = response["cursor_id"]

        assert response["starting_from"] == self.__retrieved, (
            "Result batch started from %s, expected %s" % (
                response['starting_from'], self.__retrieved))

        self.__retrieved += response["number_returned"]
        self.__data = deque(response["data"])
Send a getmore message and handle the response.
dataset/ETHPy150Open blynch/CloudMemeBackend/pymongo/command_cursor.py/CommandCursor.__send_message