There is no physical way to have your python scrip running "in the app". From what I see, you'd like the image to be processed by those Python packages. The ideal approach would be that:

1. The app saves the image somewhere (via backend)
2. Your script (python) is running somewhere on some server (AWS EC2, for example), takes the saved image from the app and processes it
3. The script saves back to the DB
4. App fetches the results (via backend)