Honestly, to me it is unreadable. Defining function inside a function inside yet another function where you use a for loop kind of function.

It requires a much different line of thinking to be applicable in the real world, which goes against historic human nature of following specific instructions, one instruction at a time.

Not really, you're looking at this very superficially. It's just an unfamiliar syntax.

If you're really interested, just try to get through that syntax once and you'll find that it's not that alien.

> Honestly, to me it is unreadable. Defining function inside a function inside yet another function where you use a for loop kind of function.

Perhaps you think the same thing about JS where that was (and maybe still is?) a common idiom. Except that people didn't give those functions names.

And for sure, it's possible to do it in all sorts of languages: python, ruby, js, go, and of course lisp

I get that the syntax is "weird", but honestly, the only two real difference is that the parens are "on the wrong side" for functions/expressions, and the indentation is truncated (the trailing side of the paren pyramid is accumulated and stuck to the end of the last functional line).

Doing that stuff in Python would further slow down an already slow language to a crawl.

Calling non-builtin functions in cPython is super expensive.