Running Python on Server and sending results to Client and vice versa
You can use Brython in the browser, it's pretty spiffy. Full dom-manipulation from python; fully compatible with libraries written in pure python. Really neat stuff. 
As for the server-side, if you want to keep it full-python, you'll need to use something like flask, bottle, cherrypy, aiohttp,...
If you find yourself struggling; maybe try starting out writing a simple socket-based microservice? You'll then be able to either farm requests out to it from any other server; or incorporate the code in your (python) server code.
Good luck!
So basically, what I want to do is have a user input some data in an HTML form or something (on client end). Have that data be carried over to a server, where the data is put through some python code and the processed result is sent back to the client. I know, I could use javascript to do this on the user side itself, but I want to experiment a bit and make use of some libraries like tensorflow, matplotlib and so on.
Also, is there some way, you know like Web Assembly to run python code on the client side. Like maybe, send data from server or have it fed by the user, and on some virtual environment type setup and processed ??
Note: I know flask exists and I've tried it, but I can't see the same flexibility as you know regular python code.
Thanks in advance