cc @cheimes @jussilehtola

A new version of black was released some time ago, 20.8b0 / 20.8b1. We are at 19.10b0 in Fedora 32 and 33. I'd like to update it in both, but it subtly breaks backwards compatibility.

Black is a code formatter with very strict rules. One of the benefit of using black is the determinism of its output. By running black on code twice, it is guaranteed (well, claimed) to produce no changes. When updating it however, new changes might appear on a codebase that was previously considered "OK".

There are several changes in formatting: https://black.readthedocs.io/en/stable/change_log.html#b0

I expect our users to prefer the latest version of black over total stability of its output.

Things that would make it more likely to grant a request:

✔️ The update doesn't change ABI/API and nothing needs to be rebuilt against the new version.
✔️ The update fixes serious bugs that many fedora users are encountering.
- mostly compatibility with new features that our users might start using with Python 3.8+.

Things that would make it less likely to grant a request:

✘ The update converts databases or resources one way to a new format.
✘ The update requires admin intervention for the service to keep working (config file format changes, etc)
✔️The update causes behavior changes (something that was denied is allowed, etc)
✘ The update changes the UI the end user sees (moves menus or buttons around, changes option names on command line)
✘ [as in "not only"] The update fixes bugs that no fedora user has reported nor would affect many fedora users (ie, fixes for other platforms or configurations).

https://bugzilla.redhat.com/show_bug.cgi?id=1908920