protected function shipment($shipment)
    {
        $data = [];

        if (is_array($shipment)) {
            if (isset($shipment['length']) && isset($shipment['width']) && isset($shipment['height'])) {
                $volumetric = (($shipment['length'] * $shipment['width'] * $shipment['height']) / 6000) * 1000;
                $actual = isset($shipment['weight']) ? $shipment['weight'] : 0;

                $data['weight'] = $volumetric > $actual ? $volumetric : $actual;
                $data['length'] = $shipment['length'];
                $data['width'] = $shipment['width'];
                $data['height'] = $shipment['height'];
            }
        } else {
            $data['weight'] = $shipment;
        }

        return $data;
    }