This set of tools will ease the development process of cmd line tools. You'll find several mixins that can be combined to construct powerful and cleaner tools.
Mixins will depend on each other sometimes. The interfaces for all of them are carefully defined.
Your task here is to extend the project. All tests in this project are already passing. We've laid out some ideas (you'll find them in the mixins modules) but you can use your own.
It's important to note that, for this project, you're in charge of writing tests. You have to start thinking in a more TDD fashion.
Start with the commands.py file to see a few examples of command implemented using mixins.