thing is you return float although the result always is an integer value

Why are we supposed to return ['None'] if there is no fitting string in the List. It makes absolute sense to just return an empty List if there is NO match in the List.
Also there could be the STring 'None' in the list with searchword 'no' and you wouldn't know, was there no result or is 'None' the only result...
There are so many Katas where you have to do some weird stuff when having an edge case instead of just doing the obvious and i don't mfing get it.
I know it shouldn't bother me, but it really makes me mad, probably that is the purpose........ fy

case 1: return "1!/0!";

For this purpose string formatting was introduced

yeah, double negative

genius! thank you!

Old katas tend to have skewed difficulties

that`s some next level stuff

Mathematically, it the same, but sometimes, we lose sense with over-refactoring.

Yeah could have simplified even more like that, to me kata 7 you could make it straightforward and easy to read. If you interested on golf solution, yes, we could use this or even better came out with an equation for the number lines.

Anyways, thanks for the note, Hope keep it here for future reference.

You can use lambda.

This is the specification decided by the author, though it is not best practice and has not been corrected accordingly during beta phase, hence it is too late to enforce such changes since it will invalidate all solutions in 20++ languages

is genius bro