code: static public function isDone(ShipmentInterface $shipment)
      {
          if ($shipment->isReturn()) {
              if (static::STATE_RETURNED === $shipment->getState()) {
                  return true;
              }
          } elseif (static::STATE_SHIPPED === $shipment->getState()) {
              return true;
          }
  
          return false;
      }
docs: Returns whether the given shipment (or return) is a done.
  
  @param ShipmentInterface $shipment
  
  @return bool
  
  @TODO remove
  @deprecated No longer used