Thanks a lot, that's a great intro to many useful tools.
I have 2 questions.<p>Managing dependencies<p>"If you’re developing a library, use nothing. Let your users decide, and give them as much flexibility as possible to maximize compatibility (don’t pin, unless to exclude some known-to-fail version ranges)."
What does this "nothing" contain? :-) A `requirements.txt`?
Do you test the library with various versions of that dependency (e.g. with tox)?
Docker<p>"Using a virtual environment inside a Docker container is perhaps over-the-top, but it provides extra isolation from the base image’s own Python dependencies, and the entire /venv folder can be copied over between stages if you need."<p>Do you have some use cases in mind when this can be handy?