There seems to be a regression in pytest version 7.3.x when a walrus operator is used in an assert line.
Code:

import json
import pytest

def test_json_encoder():
  assert (object:="foo") in json.dumps(object)

Fails the test with error:

UnboundLocalError: cannot access local variable 'object' where it is not associated with a value

in pytest version 7.3.x, whereas with pytest version 7.2.x it passes successfully. My Python version is 3.11.

Looks like it has to do with PR #10758.