My personal opinion is that `list_` is among the worst possible variable names (together with `bar` and `foo`). It's non-descriptive, ugly, hard to recognize, looks scary to beginners and maybe worst of all it's easy to forget the underscore when typing.

That's exactly what he's used, but with angle brackets around it. What do you think he should have done instead.

Good point. For list, one could still use the name "lst" and get the point across.