Hi all, Flake8 released a new version recently, causing our test suite to break on travis and appveyor, where we install the latest version of flake8 during setup for the test run. I've issued a pull request which should fix the travis and appveyor tests. It would be nice to get this in quickly to stabilize our test suite. https://github.com/yt-project/yt/pull/1592 Thanks for your attention, Nathan