sets are unhashable

[Skaperen]

why are sets unhashable?

[Windspar]

Probably because sets are mutable. You need immutable objects.

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simple solution is to wrap it with a tuple.

a[tuple(set([1,1,4,4,4,4,5,]))] = 1

[ichabod801]

The simple solution is to use a frozenset.

[Skaperen]

so how can i get any one element from a frozenset? with a mutable set i would pop one and put it back in. but i see no methods to get something out of a frozenset. i guess i just have to make it into a regular set or a tuple.

  some_arbitrary_element = tuple(my_frozen_set)[0]

assuming it isn't empty.

[ichabod801]

Why do you want to get a random element of something you're using as a key?

[micseydel]

so how can i get any one element from a frozenset? with a mutable set i would pop one and put it back in.

Just do next(iter(any_iterable)). Works for set, frozen set, tuple, list, etc. Please don't use mutations to achieve a result which doesn't need it, god kills puppies when you do stuff like that.

[Skaperen]

i'm not using it as a key per se, but using the set as a non-duplicating collection. get an element out is to check what types the set probably has (to avoid a full test of everything if the random item shows it is not needed)