Comment by gpderetta

Yes, the best way to understand python closures is that scopes are first class objects in python (accessible via locals()) and closures close over the containing scope itself, not the single variables.

Also worth keeping in mind that, AFAIK, there is one scope per function, which differs from other languages that can have nested scopes inside a function. I think the list comprehension is the only exception in python3, which was changed so that names no longer leak out of it, which was frankly insane in py2.