def _send_complex_request(self, request):
        """Send a request via the USB control request endpoint, rather than as a
        bulk transfer.
        """
        self.device.ctrl_transfer(0x40, self.COMPLEX_CONTROL_COMMAND, 0, 0,
                self.streamer.serialize_for_stream(request))
Send a request via the USB control request endpoint, rather than as a
        bulk transfer.