Hi,
while investigating another issue I came across this issue:
The last of these commands provokes an KeyError.
import importlib
import owlready2 as owl2
importlib.reload(owl2)
This is IMHO undesired behavior.
See also the notebook [1] for the informative traceback and a way to mitigate the problem.
[1]
https://nbviewer.ipython.org/github/cknoll/demo-material/blob/main/expertise_system/owlready_demo4.ipynb
Best, Carsten