<div id="comment:0"></div> pep8 refresh also one change about annotation CC: @tscrim @kwankyu @kliem @slel Component: **combinatorics** Author: **Frédéric Chapoton** Branch/Commit: **[`722dd2f`](https://github.com/sagemath/sagetrac-mirror/commit/722dd2f2900510f1d425aa17ee5751bf7105c8e4)** Reviewer: **Travis Scrimshaw** _Issue created by migration from https://trac.sagemath.org/ticket/34545_