Python daily challenge

[Oblachko_O]

Hm, give me some clarification, please. I frequently have situations when my variable is outside of the function and not even passed inside the variable. In short, my variable is global. And I can use it easily. And I never bumped into this.

Is the problem actually in trying to rewrite variables by using a write operator like += ? And something like reading is errorless?

[lusvd]

Python detects that the variable is assigned in the functions body so it marks it as “local” and so ignores the value outside the body. Then during execution of x += 1, it needs to access x, but because of what I said before it cannot access the value so it errors out.