"External" is relative; at home, I can install whatever I please, although I do prefer to stick to what is included with Debian stable, which is pretty comprehe

"External" is relative; at home, I can install whatever I please, although I do prefer to stick to what is included with Debian stable, which is pretty comprehensive (it includes pychecker, pyflakes, pylint and python-contract). And indeed, mypy is there to! Thanks for the pointer! At work, we are limited (for the most part) to what is included in RHEL repositories, and even more by the fact we are still on 6.9 on some projects. Hence why I mentioned python-contract, as it's not in RHEL repos (that I could find). Thankfully pyflakes/checker/lint are. I will have to check for mypy.