@property
    def duration(self) -> timezone.timedelta:
        delta_start = timezone.timedelta(
            days=self.created_on.day,
            minutes=self.created_on.minute,
            seconds=self.created_on.second,
        )
        delta_end = timezone.timedelta(
            days=self.last_updated.day,
            minutes=self.last_updated.minute,
            seconds=self.last_updated.second,
        )

        return delta_end - delta_start