Format SKU

Hi,

I am upgrading my plugin from nopCommerce 3.9 to nopCommerce 4.1. How do I fix this error?

        foreach (OrderItem ov in od.OrderItems)
        {
            if (!String.IsNullOrEmpty(ov.AttributesXml))
                odd.Sku = ov.Product.FormatSku(ov.AttributesXml, _productAttributeParser);
            else
                odd.Sku = ov.Product.Sku;
  }

'Product' does not contain a definition for 'FormatSku' and no extension method 'FormatSku' accepting a first argument of type 'Product' could be found (are you missing a using directive or an assembly reference?)

You can use search to find items - search for FormatSku

//SKU
var sku = _productService.FormatSku(p, orderItem.AttributesXml);