[Python-Dev] Accepting PEP 572, Assignment Expressions

[Random832]

On Wed, Jul 11, 2018, at 20:10, Guido van Rossum wrote:
> As anticippated, after a final round of feedback I am hereby accepting PEP
> 572, Assignment Expressions: https://www.python.org/dev/peps/pep-0572/

I know everyone else is probably sick of discussing this (I somehow completely missed the discussion until it was almost done) but I have a question...

Why does this not allow assignment to attributes and subscripts? I think this is, at least, surprising enough that there should be a rationale section explaining it in the PEP. As it is, it's barely even explicitly stated, other than the use of 'NAME' in a few places and an offhand mention "and [the assignment statement] can assign to attributes and subscripts."