What is being repeated that shouldn't be in this solution?

have you used timeit to compare the performance of your Counter() solution with this one? I personally believe that your solution could be 10X slower.

Repeating code doesnt automatically ruin a solution. In this case it is actually very readable and writing this in another way would make it unclear for no reason

But useless =~)

https://www.codewars.com/kata/reviews/581f12505b2f0b5b05000079/groups/5eb0b5d00af08a00019fe6af

I'm not entirely sure, but a hint might be that the numbers always increment by 3.

Not dirty, but yes working in Python 2 only

just 2)

thank you i have checked and refactored my solution