@nathanleiby @mohit does pyflakes do auto-correction? What I like about pep8 is that autopep8 can be configured to run on save and fix common errors (similar to gofmt).

@nathanleiby re testing: the general approach this doc recommends is having checks run alongside tests (see the introduction), however the approach does not go as far as making the tests fail. I think step one is getting all of our repos to a place where these checks are easy to run and run successfully. My ideal world is one where there's a separate [commit status](https://github.com/blog/1227-commit-status-api) reported for running these checks, which essentially elevates them to the status of a test failure.