Not sure why people voted this best practice, but very clever

Worst practice but clever! :-D

You're welcome :)

Oh, I See! Thanks so much, perfect explanation. :D

Big brain, but man that's brutal to read. What was the runtime?

2*n == n*2
Yours seems slightly faster indeed, but around 10-20% depending on the size of the list.
And partly because of the extra layer of itemgetter.

For example with the same random tests as the kata and the same list of 1_000_000 tests for each one, I get the following results:
Mercy: 3.399389314651489 seconds
Oleg: 3.032890796661377 seconds
rowcased: 3.238804864883423 seconds

And while obviously not unreadable, your code takes just a little longer to get for a newcomer.

O(2n). Not the best one

O(2n). Not the best one

variable names can be improved a bit. well done.