Having file websocket_server.py and webscoket_service.py to run websocket I do python websocket_server.py
How show I configure custom file watcher so when I modify webscoket_service.py, my websocket server being restarted
You can simply pass autoreload=True or debug=True (which does autoreload and some other things) to your Application constructor.
Create file watcher that will restart websocket server when specific files modified