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Comment by iainmerrick | Hacker News Reader

Not often, but when you do want to do it, it’s frustrating (and unusual for Python) that the natural and obvious way doesn’t work.

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When I read this my first thought was "you should use a FrozenDict", but looking into it, it seems that it doesn't exist; I assumed so because of FrozenSets (hashable sets).

You can still create a hashable key from a dict with FrozenSet(mydict.items()).

Ah nice. Yes that last suggestion is probably a more simple and elegant approach than anything I'd mentioned / thought about

You don't really need a FrozenSet if you're already willing to iterate over this dictionary. You can just use a tuple, which is also hashable.

tuple(d.items())

That depends on the order in which the values are are returned by items(), which you likely do not want.

    >>> tuple({1:2,3:4}.items()) == tuple({3:4,1:2}.items())
    False
    >>> frozenset({1:2,3:4}.items()) == frozenset({3:4,1:2}.items())
    True

Good point

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