Jukka Lehtosalo 5be9c91518 freezegun: Fix __exit__ and remove union return types (#4491) ...

These caused false positives, for example in code like this:

```
    with freeze_time(None) as ft:  # False positive here
        ft.tick(3)  # False positive here
```

2020-08-28 16:50:05 +01:00

..

2

upgrade black version (#4486)

2020-08-26 18:36:01 +02:00

2and3

upgrade black version (#4486)

2020-08-26 18:36:01 +02:00

3

freezegun: Fix __exit__ and remove union return types (#4491)

2020-08-28 16:50:05 +01:00