Comment by bjourne

Flask is about the most beautiful Python code you can write. Check out any other Python framework and they may have a decent api, but on the inside it is messy and confusing. Reading Flask source code on the other hand is a joy. There's no crazy stuff and few convoluted pieces + lots of comments so it is really easy to hack something if you must. Any Python coder who wants to improve their game definitely should study Flask because it is such a great piece of software engineering.