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Collections are a way for you to organize kata so that you can create your own training routines. Every collection you create is public and automatically sharable with other warriors. After you have added a few kata to a collection you and others can train on the kata contained within the collection.
Get started now by creating a new collection.
Test cases still borken for python.
2^n is correct if you assume unique elements in the list.
I tried 2**(len(set(lst))) as the answer and it didn't like it in the test cases,
so they are assuming each item is unique.
Python version has no tests.