UnicodeDelimitedTupleAttribute does not support datetime.datetime objects

The deserialization of the UnicodeDelimitedTupleAttribute does not support `datetime` objects and results in the error: "TypeError: 'str' object cannot be interpreted as an integer"

It would be useful for this type to support `datetime.datetime` objects.

Locate UnicodeDelimitedTupleAttribute and reproduce deserialization with a datetime.datetime value to confirm the reported TypeError. Done means datetime.datetime values deserialize successfully without the string-to-integer error; the payload does not name a file or test to run.

Written by the indexing model from the issue text.