In addition, I would like
>>> d = dict()
>>> d[x=1, y=2] = 5
to work. It works out-of-the-box for my scheme. It can be made to work with a subclass of dict for the D'Aprano scheme.
This raises the question
about this advantage (I agree it could be an advantage): is providing such a subclass really such a heavy lift? Additionally and related: what would be the real world advantages of d[x=1, y=2], where d is just a vanilla dict, working right out of the box?
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