Expr vs Expression

[Matthias Bussonnier]

I just discovered that ast as Expr and Expression nodes, which appear to be different.
I don't see both described, and I'm not sure about the different. It might have to do with Eval vs exec and top-level vs not.

[Thomas Kluyver]

Hey Matthias.

Expression is a top-level node, which are all described separately under Modes. That section describes the difference between Expression and Expr, but it would be good to have a note under the Expr node as well.