macOS python PDF service denied access in macOS Catalina

Question

Since many years I have been using a Python script, to add a "virtual printer" to my macOS printing dialogue and print on a PDF stationery from any application.

The script is placed within ~/Library/PDF Services, took sys.argv[3] as an input file, merged the input file with a given PDF stationery and saved it in ~/Downloads.

I was happy until I updated to macOS Catalina and always got this message from Console:

Sandbox: Python(30225) System Policy: deny(1) file-read-data /Users/me/Documents/stationery.pdf

It seems that, due to the new permissions in macOS Catalina, the script cannot access the stationery file anymore. Python however has full hard disk access.

If I run the same script from the Terminal, everything works fine.

How can I grant the script access to the required document (/Users/me/Documents/stationery.pdf) when executed from withing the printing dialogue?

Answer 1

EDIT:

This problem seems to have been fixed in Monterey: python scripts will now correctly run as PDF Services.

(Of course, they're removing python, so you'll have to install your own. Swings and Roundabouts.)