https://docs.python.org/3/tutorial/classes.html for the docs that Roscoe is talking about.

So the sentence is technically correct, it just takes careful reading to grasp what's being said. There are "at least three nested scopes", but there can be *up to* four scopes. Since "the scopes of any enclosing functions" is not necessarily true for all code scopes, you end up with at least three, but possibly four scopes.

Obviously the wording could be clearer, so if you want to sign the CLA, Roscoe, and propose a rewording that would be appreciated!