<div id="comment:0"></div> this is about E502 the backslash is redundant between brackets CC: @tscrim @kwankyu @kliem @slel Component: **refactoring** Author: **Frédéric Chapoton** Branch/Commit: **[`0f27e53`](https://github.com/sagemath/sagetrac-mirror/commit/0f27e53660c5ddcdf97dcf6ce194064ea1ca0371)** Reviewer: **Travis Scrimshaw** _Issue created by migration from https://trac.sagemath.org/ticket/34660_