Black has some changes: https://black.readthedocs.io/en/stable/change_log.html#b0 - in particular:

• re-implemented support for explicit trailing commas: now it works consistently within any bracket pair, including nested structures (Facets: show counts for null #1288 and duplicates)
• Black now reindents docstrings when reindenting code around it (Document recommendations for plugin authors to design URLs #1053)