In this PR: https://github.com/twisted/twisted/pull/1365 pycodestyle was disabled in trunk in order to make it easier to merge changes and not have pycodestyle error out, due to the code not meeting existing Twisted style guidelines. So this means that the old pycodestyle is not enforced in trunk. In this PR: https://github.com/twisted/twisted/pull/1356 a `.git-blame-ignore-revs <https://github.com/twisted/twisted/pull/1356/commits/294aaf3eeaba41d64a80644bd3355a9b153047e8>` file was added to the tree. I guess in future, if the entire tree is reformatted, then we can add that git SHA for the PR which reformats the tree, so that that revision will be ignored during a `git blame`. There is this pending (over 1 year) PR to add black to CI: https://github.com/twisted/twisted/pull/1134 There are some comments in there related to documentation changes. Can the non-documentation changes be pulled out of PR 1134 and merged to trunk now? I guess whenever black is merged to trunk, then a follow-up PR to update `.git-blame-ignore-devs` would be required? -- Craig