[Python] The most efficient way in Python to test if an element belongs to certain category

So I have a loop in Python and I want to test if elements belong to some category:

for element in some_iterator():
if element in collection:
do_something()


Question: what should be the class of collection for this code to be optimal?

I'm guessing that if I construct the collection outside of function, the best one would be set. But if I want to use a literal, the set will need to be constructed on every call.

How to balance between construction time and testing time? Is list the best option after all?

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