async def modify_otr_status(self, off_record):
        """Set the OTR mode of this conversation.

        Args:
            off_record: ``True`` to disable history, or ``False`` to enable it.

        Raises:
            .NetworkError: If the request fails.

        Returns:
            :class:`.ConversationEvent` representing the change.
        """
        if off_record:
            status = hangouts_pb2.OFF_THE_RECORD_STATUS_OFF_THE_RECORD
        else:
            status = hangouts_pb2.OFF_THE_RECORD_STATUS_ON_THE_RECORD
        try:
            response = await self._client.modify_otr_status(
                hangouts_pb2.ModifyOTRStatusRequest(
                    request_header=self._client.get_request_header(),
                    otr_status=status,
                    event_request_header=self._get_event_request_header(),
                )
            )
            return self._wrap_event(response.created_event)
        except exceptions.NetworkError as e:
            logger.warning('Failed to set OTR mode: {}'.format(e))
            raise
Set the OTR mode of this conversation.

        Args:
            off_record: ``True`` to disable history, or ``False`` to enable it.

        Raises:
            .NetworkError: If the request fails.

        Returns:
            :class:`.ConversationEvent` representing the change.
        
hangups/conversation.py