PEP 8 Speaks
A GitHub app to automatically review Python code style
...Style issues get lost in the long CI build logs and the authors of the Pull Requests are not notified about them (unless flake8 is strict about failing the build). Thus, new issues are overlooked and introduced in the project. PEP 8 Speaks can read the setup.cfg file and adopt your already existing flake8/pycodestyle settings. PEP 8 Speaks is free of cost. By default, it can not work on private repositories.