if (something as x) == other: # can now use x.
Interesting. I'd definitely prefer that to the C-style inline assignment syntax: I think it reads better, and there's less chance of the Accidental Assignment Instead Of Comparison trap that has plagued other languages.
However, allowing this "something as x" syntax for assignment would cause confusion with the "with contextmanager as x" scenario. "as" was chosen in their case because the expr contextmanager is not assigned to x. While I do like the "as" syntax too, I have not endorsed it for the above reason. However, this does show that using the "as" makes this somehow pythonic looking, and there must be an alternative that keeps this far enough away from the assignment expressions in other languages so as to avoid the trap you mention.
I remain to be convinced that inline assignment is enough of a win in general, but if implemented, that's the syntax I'd want.
Cheers, Jervis