Update flake8 to 3.9.1#324

pyup-bot wants to merge 2 commits intomasterjoaogarciadelima/libpythonpro:masterfrom

pyup-update-flake8-3.7.9-to-3.9.1joaogarciadelima/libpythonpro:pyup-update-flake8-3.7.9-to-3.9.1Copy head branch name to clipboard