As another commenter mentioned: Django, DRF, Flask
But unmentioned... The old titans of Pyramid, Pylons, CherryPy, Bottle, Tornado, wheezy, web2py, and more.
You have Django and DRF and Flask. DRF is, by far, the best designed framework for building APIs in any programming language I have ever seen, and I've at this game for a long time.
Python has substantially fewer packages where the community rallies around them and keeps them as best-in-class. SQLAlchemy, DRF, factoryboy, requests, etc., are all incredible one-stop-shops for the vast majority of use cases.
You don't need 15 libraries for doing HTTP requests. You just need one good one that does the job so you never have to think about the problem ever again. Python excels at this class of libraries and by comparison npm has appalling choices.
When you think about and iterate judiciously in a problem domain over a decade instead of trying something different every day to see what sticks, you'll see you can get remarkably far.
Let me see, you've got Django, DRF, Flask, Flask-Restful, Flask-Restplus, Flask-API, sanic, pyramid, Cornice, hug, falcon, eve, bottle, tornado, aiohttp, vibora, weppy, starlette...
Those are just some that I've picked out of my head.
Routing requests and managing HTTP fundamentals is a solved problem. There is literally zero value in adding another framework when the real complexity is in business logic.
Django does routing, forms, ORM, templates, APIs, GIS, you name it. Flask is more minimialist and expects third-party package for this.
Django also has a very extensive ecosystem of libraries for managing the common web use cases.