I am sure this has probably been brought up before... but You CAN do the calculation with a calculator... it's not an unreasonably large number. The numerical value of this argument: ([4, 3, 6] comes out to 68719476736. That expected result should be 6. Why is this Kata's expected ouput wrong?
" ([4, 3, 6], 4)) .

In the kata description it says this: E. g., with the input [3, 4, 2], your code should return 1 because 3 ^ (4 ^ 2) = 3 ^ 16 = 43046721.

that looks like a list to me! It did not mention anything about arguments being in the form of both lists or lists within tuples ! why was this information left out?

No matter what I do to handle this (I used a recursive function to "flatten" the list), but no matter waht I do, I cannot get ([0,0,0],0) to return the expected 0. It always returns a 1.

Are these not nested lists? The arements have arrays within the lists! lists within lists.

test_data = [
        ([], 1),
        ([0, 0], 1),
        ([0, 0, 0], 0),
        ([1, 2], 1),
        ([3, 4, 5], 1),
        ([4, 3, 6], 4),
        ([7, 6, 21], 1),
        ([12, 30, 21], 6),
        ([2, 2, 2, 0], 4),
        ([937640, 767456, 981242], 0),
        ([123232, 694022, 140249], 6),
        ([499942, 898102, 846073], 6)

My comment on this kata is that the description is a little mis-leading! Nowhere in the description does it mention that testing will include arguments that hare nested lists! Therefore my current solution gets errors. Does this solution require recursion?

This brevity amazes me... it seems like the most efficient solution (though perhaps not as readable) but I do have one question that puzzles me. How does this regular expression determine if the length of s is even or odd? How does it know that it only needs to add a "_" character if the last pair character pairing in the string is solitary?