Django has good tutorials, I don't know about building "one app" though. I'm sure you can find some of lesser quality; Hartl's tutorial is one of the very best.

If you don't mind drawing out your learning process, you could walk through Hartl's tutorial and do the equivalent in Python (probably with much help from google). So you couldn't use his code examples, but you could set up the same DB structure, the same types of tests, etc, and hit all the important parts of the web dev process.

Edit: found this in another comment below. Just thought I'd include it in case you gloss over it! https://blog.miguelgrinberg.com/post/the-flask-mega-tutorial...

Django Unleashed is written as a step-by-step guide to building a single Django project. The link below has links to Amazon or to Pearson's own site (DRM-Free!).

http://django-unleashed.com/

Full Disclosure: I'm the author.

If you're looking to go nuts, I recommend reading the first twelve chapters of Django Unleashed, following it up with Harry Percival's Test Driven Development with Python book (also written as a step-by-step guide), and then finishing Unleashed.

http://chimera.labs.oreilly.com/books/1234000000754/index.ht...

Two Scoops of Django (not a guide) is great to have after that.

https://www.twoscoopspress.com/products/two-scoops-of-django...

Hope that helps!

The closest thing I know of is Test-Driven Development in Python. http://chimera.labs.oreilly.com/books/1234000000754

It goes through making an app in Django, but is heavier on TDD than Hartl's book.

For what it's worth, it's fairly agnostic when it comes to languages or frameworks. Yes, you'll learn Rails, and some Ruby on the way, but the intent is to learn web development from the ground up. You'll learn concepts that will apply to anything else you might be using. It's invaluable, and a great place to start with web development.