I echo this sentiment. I've learned a ton of Python from reading the Django source code. There's definitely something to be said about the DSF and the many contributors over the years who've worked tirelessly to push the envelope with the framework (and the ORM, in particular) while also keeping the codebase sane. It's not all perfect, but it's about as good as it gets for FOSS with so many people chiming in over more than a decade