When we import datetime from the datetime module, we get the datetime class,
not the module. This caused isinstance() checks to fail when checking against
datetime.date (which doesn't exist when datetime is a class).
Solution: Import date explicitly from datetime module and use it in isinstance
checks. Order matters - check datetime before date since datetime is a subclass
of date.
Fixes: "isinstance() arg 2 must be a type, a tuple of types, or a union"
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Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>
alex
4f4ba6af51