ShipmentCollection::getSystemShipment

public function getSystemShipment()
{
	/** @var Shipment $shipment */
	foreach ($this->collection as $shipment)
	{
		if ($shipment->isSystem())
		{
			return $shipment;
		}
	}

	/** @var Shipment $shipmentClassName */
	$shipmentClassName = static::getItemCollectionClassName();
	$shipment = $shipmentClassName::createSystem($this);
	$this->addItem($shipment);

	return $shipment;
}