Django and Flask are the two most popular Python frameworks that you can use for fast web development. Django is better suited for enterprise-grade web applications that expect to see exponential growth potential and that might get much more functionalities in the future. Flask is better for smaller SPAs that have static content and that you don’t expect to change a lot.
Django is a “batteries included” framework. Here, you’ll find the admin panel, ORM and much more. Thus, the developer can source all those modules without virtually no brand new code, and they can instead focus on writing those components that are completely unique.
It works extremely fast and integrates perfectly well with other technologies in your stack.
Python isn’t that fast and if you mess up the architecture in Django, the app might be lagging. But there are tools to check for those bottlenecks and fix them.
If you just want to create a static SPA, you might spend too much time configuring the stuff that you won’t actually need to use.