gh-36461: fix the linters again
Fix the broken linters again
broken just recently in` graphs/graph.py` #36354
### :memo: Checklist
- [x] The title is concise, informative, and self-explanatory.
- [x] The description explains in detail what this PR is about.
URL: https://github.com/sagemath/sage/pull/36461
Reported by: Frédéric Chapoton
Reviewer(s): Frédéric Chapoton, Kwankyu Lee
