/**
  * @param OrderInterface $order
  *
  * @return ShipmentInterface
  */
 private function getOrderShipment(OrderInterface $order)
 {
     if ($order->hasShipments()) {
         return $order->getShipments()->first();
     }
     try {
         /** @var ShipmentInterface $shipment */
         $shipment = $this->shipmentFactory->createNew();
         $shipment->setOrder($order);
         $shipment->setMethod($this->defaultShippingMethodResolver->getDefaultShippingMethod($shipment));
         $order->addShipment($shipment);
         return $shipment;
     } catch (UnresolvedDefaultShippingMethodException $exception) {
         return null;
     }
 }