Submittable Event - ImportError: cannot import name FileNotFoundError

So I have just edited the core doctype Event to be submitted.

I have submitted an event but when Cancelling and confirming the cancellation, the following error appears:

Message: Did not cancel

the only button available is Close. After closing the notification pop-up, the following error appears:

Server error: ImportError: cannot import name FileNotFoundError

This happens on the following erpnext instance:

ERPNext: v12.1.2 (version-12)

Frappe Framework: v12.0.10 (version-12)

… any idea how to fix this ?

This continues to be an issue and a potential bug - any information from anyone ?