How to process video dynamically depending on its parameters?

Question

Python

The user uploads a video, and based on what kind of video it is (horizontal or vertical, and what aspect ratio it has), I process it in a certain way (processing is done using ffmpeg). Example of changeable parameters:

• If the video is horizontal: Change resolution and save
  
• If video is 1:1 aspect ratio: Resize and save
  
• If the video is vertical (but not 1:!) : Set the aspect ratio to 4:5, change the resolution and save.
  

I need to figure out how to get information about the video in the code (python), and based on this, pass the appropriate ffmpeg command. Or is it done in some other way? For example, Instagram, how it determines how to process videos, because users upload videos with different aspect ratios, orientations, and so on.

Answer 1

What's wrong with using something like this:
Then, already in python, the written logic must decide how to pull out what is needed from the answer and apply the encoding settings.