"timeit" test found that "Counter" took more time.

Fixed

fixed by mauro-chabby combo

Good that you wrote it. I had the same problem :D

1 -> 2 -> 3 -> None should equal 1 -> 2 -> 3 -> None

0 -> 1 -> 4 -> 9 -> 16 -> None should equal 0 -> 1 -> 4 -> 9 -> 16 -> None

Oh data type was str, not int -> error message is a bit obscure

1 -> 2 -> 3 -> None should equal 1 -> 2 -> 3 -> None

Approved, thanks!

almost assembly

You actually don't need parentheses around \1\b, you can try it and see it for yourself. Let me know if that answers your question.

Can someone please explain why the second \b occurs in the second group inside the parenthesis but not in the first one?

Abdallah

if it looks OK to you ^^

Am I okay to approve this?

One of the most evil? How so? You obviously haven't seen much C code.
Might I suggest studying the results of the IOCCC?

You'd also have to rename the function...

C: the return type should be void.