def extend_hit(self, hit_id, number, duration_hours=None):
        """Extend an existing HIT and return an updated description"""
        self.create_additional_assignments_for_hit(hit_id, number)

        if duration_hours is not None:
            self.update_expiration_for_hit(hit_id, duration_hours)

        return self.get_hit(hit_id)
Extend an existing HIT and return an updated description