private async Task <Google.Cloud.Vision.V1.ReferenceImage> CreateReferenceImage(ProductSearchClient client, CreateReferenceImageOptions opts)
        {
            var request = new CreateReferenceImageRequest
            {
                // Get the full path of the product.
                ParentAsProductName = new ProductName(opts.ProjectID, opts.ComputeRegion, opts.ProductID),
                ReferenceImageId    = opts.ReferenceImageID,
                // Create a reference image.
                ReferenceImage = new Google.Cloud.Vision.V1.ReferenceImage
                {
                    Uri = opts.ReferenceImageURI
                }
            };

            var referenceImage = await client.CreateReferenceImageAsync(request);

            return(referenceImage);
        }