It turns out that sage-shell-mode in emacs uses the variable interfaces, deleted from sage.interfaces.all in #34547. We restore that variable (which is not used anywhere in the Sage library) along with a comment.

Component: interfaces

Keywords: emacs

Author: John Palmieri

Branch/Commit: u/jhpalmieri/interfaces-emacs @ 49d4ff7

Reviewer: Matthias Koeppe

Issue created by migration from https://trac.sagemath.org/ticket/34935