def product_quantity_ordered():
    total_quantity_ordered_products = (
        Product.objects.annotate(
            total_ordered_quantity=Sum('orderproduct__quantity')
        ).exclude(total_ordered_quantity=None).order_by('-total_ordered_quantity')
    )
    result = []

    for product in total_quantity_ordered_products:
        result.append(f"Quantity ordered of {product.name}: {product.total_ordered_quantity}")

    return "\n".join(result)