__slots__ as a dict is not documented in the data model docs.

Starting with 3.8, __slots__ can be a dict, mapping slot names to docstrings. See https://docs.python.org/3/whatsnew/3.8.html#inspect

This came up in issue #113878 for adding docstrings to slots in dataclasses.

The data-model docs do mention this, in the fourth-from-last bullet point on __slots__. I added docs for it in

(See discussion in that PR for why it was decided not to have more prominent documentation for this feature.)

@rhettinger

@rhettinger, I'm somewhat confused by your comment in #113878 (comment), since you reviewed that PR :)

@AlexWaygood

Ah, good point @AlexWaygood. I clearly didn't read far enough, and it's true that a dict with str keys is an iterable of strings.

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