Question: in the list comprehension example, is `x` defined outside the loop comprehension? Will it overwrite an existing `x`? Or is it like `z` and only visibl

Question: in the list comprehension example, is `x` defined outside the loop comprehension? Will it overwrite an existing `x`? Or is it like `z` and only visible inside the loop comprehension? The latter would make more sense, I think.