Just doing the basic obs WebSocket examples I've found. In the OBS client it looks like it briefly connects but then they all end up with this error:
Exception has occurred: KeyError
'status'
File "obswebsocket_tests.py", line 3, in <module>
client.connect()
Here's my code:
import obswebsocket, obswebsocket.requests
client = obswebsocket.obsws("localhost", 4444)
client.connect()
v = client.call(obswebsocket.requests.GetVersion()).getObsWebsocketVersion()
print(v)
client.disconnect()

The latest release of the obs-websocket-py library (0.5.3) was on December 20th 2020.
Version 28 of OBS, released on August 3rd 2022, comes with the new WebSocket plugin version 5.
From their blog post:
You will need to separately install version 4 of the WebSocket plugin, from their release page.