Thespian has several supported transports (TCP, UDP, Queue) for multi-process Actors, but websockets is not one of them. To utilize websockets it would be necessary to be running Python Thespian Actors on both sides of the websocket connection, which is not something I've anticipated needing.
The example you referenced above provides an Actor which acts as a bridge between other Actors and a Websocket, passing messages from other Actors to the Websocket and vice-versa. This may be the best way to obtain the functionality you are looking for.
Regards,
Kevin