Those strings methods are indeed more clever than I thought, which was "it won't replace/match a pair if in between are other brackets". Well, it turned out that it still works and for me this solution is the most clean one. I wonder how performant is it and why you use +2 in the loop? I have tried to loop over len(str) and it works as well.

I haven't seen yet such usage of an . in an import statement. It this rather simple example it makes things much more readable.

I'm not so far and right now I'm struggling a bit with the solution for the Reduce Directions kata.

Hi, Thanks for the comment. Yes, the named return value here is just for reducing the number of lines, and make the code enjoyable, since it s just 9 lines of code. I did enjoy writing it. Right now I am thinking about n-queens on 1000x1000 chess board to solve it under 10 seconds. let me know if you have a 10-second solution :)

Yeah, as I recall that scenario threw me at first too. In my first attempt I wasn't doing the b < 0 check inside the loop, only ckecking for b == 0 at the end.

Why does it work?

I came up with the same concept but I cannot handle a case with unmatched parenthesis like ())(. It turned out that it's much easier than I thought.

Yeah, me too. It can be sometimes really so simple.

That's a pretty neat solution. I wanted something similar but I couldn't think of a good solution to retrieve a searched value of ok. The usage of named return I find also quite clever but at the same time it's not very obvious (I didn't know that a variable inside the loop can be named the same as the returned varsiable).