tzinfo lost in UTCDateTimeAttribute

[NodoFox]

After getting ValueError, parse is called which always returns UTCDateTimeAttribute with tzinfo=tzlocal() even if the saved item had tzinfo=UTC

https://github.com/pynamodb/PynamoDB/blob/master/pynamodb/attributes.py#L553

        try:
            return datetime.strptime(value, DATETIME_FORMAT)
        except ValueError:
            return parse(value)

[ikonst]

@NodoFox Do you remember in which cases the ValueError would occur? Is this trying to parse times that weren't written by PynamoDB?