We continue after #32675 and #32668, here in rings, matrix, libs, interfaces, manifolds
CC: @kwankyu
Component: refactoring
Author: Frédéric Chapoton
Branch/Commit: a6c9428
Reviewer: Kwankyu Lee
Issue created by migration from https://trac.sagemath.org/ticket/32682