Please provide the code that you have so far.

Other games examples...
https://github.com/Pythonista-Tools/Pythonista-Tools/blob/master/Games.md

Yes. My point was about converting from Python datetimes to Objective C datetimes.

To convert from Python datetimes...

from datetime import datetime
print(f'{datetime.now():%Y%m%d %H:%M}')

Apple works hard to make sure that one iOS app can not "drive" another iOS app for security reasons.

If you have the source code for both apps you can do things or if one app exposes URLs then the other can use those URLs to drive things.

With iMessage, you can build a message from another app but you can NOT click the send button. This is a good thing from a security perspective.

how to specify a specific calendar

What exactly does that mean? Can you provides some sample code of what you have working so far with a description of how you want to change it?

The Apple docs for this function call are at https://developer.apple.com/documentation/eventkit/ekeventstore/1507479-predicateforeventswithstartdate?language=objc

You mean that packages that support both Python 2 and Python 3 (like requests) are not interesting?
Also packages that have no trove classifiers are not interesting?
Clearly there are more than 2,000 PyPI packages that are interesting.

https://pypi.org currently hosts 250,000 packages so I doubt that anyone is going to write down the subset that is pure Python.

Please provide some sample code that raises the error so that we can all see what you are seeing.