["python","datetime","mocking","pytest"]
How to monkeypatch python's datetime.datetime.now with py.test?

I need to test functions which uses datetime.datetime.now(). What is the easiest way to do this?
You need to monkeypatch datetime.now function. In example below, I'm creating fixture which I can re-use later in other tests: import datetime import pytest FAKE_TIME = datetime.datetime(2020, 12, 25, 17, 5, 55) @pytest.fixture def patch_datetime_now(monkeypatch): class mydatetime(datetime.datetime): @classmethod def now(cls): return FAKE_TIME monkeypatch.setattr(datetime, 'datetime', mydatetime) def test_patch_datetime(patch_datetime_now): assert datetime.datetime.now() == FAKE_TIME