protected function setProductField()
    {
        $sProductID = array_get($this->arImportData, 'product_id');
        if ($sProductID === null) {
            return;
        }

        //Find product by external ID
        $obProduct = Product::withTrashed()->getByExternalID($sProductID)->first();
        if (empty($obProduct)) {
            $this->arImportData['product_id'] = null;
        } else {
            $this->arImportData['product_id'] = $obProduct->id;
        }
    }