Raymond Hettinger firstname.lastname@example.org added the comment:
I concur that the one warning is enough. Implementations have been given wide latitude in this regard. Even within CPython there is not much uniformity -- some funcs/methods don't accept keywords, some will disregard keywords, and others may have keywords that are different from the name in the docs.
I believe it would be a mistake to make to lock in the present state of accidental implementation details by documenting them in the main docs.
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