PlexTraktSync: Installing requirements.txt fails on Python 3.9

I’m using Python 3.9 on the Mac that I’m running this script (it’s running macOS 10.15.7). Both pip and pip3 are pointed to /Library/Frameworks/Python.framework/Versions/Current/bin/python3, which at the moment is /Library/Frameworks/Python.framework/Versions/3.9/bin/python3.

Running pip3 install -r requirements.txt failed at the part where it’s trying to install typed_ast, version 1.4.0. I found this GitHub issue where it appears this was resolved in version 1.4.2. I modified requirements.txt to include typed-ast==1.4.2 instead, and was able to install successfully. The Trakt/Plex sync works OK now.

I don’t know the greater implications of this, so I figured I’d submit an issue before a pull request. If you’d like a pull request for this, just let me know.