code: public Observable<TrendingImages> trendingAsync(TrendingOptionalParameter trendingOptionalParameter) {
          return trendingWithServiceResponseAsync(trendingOptionalParameter).map(new Func1<ServiceResponse<TrendingImages>, TrendingImages>() {
              @Override
              public TrendingImages call(ServiceResponse<TrendingImages> response) {
                  return response.body();
              }
          });
      }
docs: The Image Trending Search API lets you search on Bing and get back a list of images that are trending based on search requests made by others. The images are broken out into different categories. For example, Popular People Searches. For a list of markets that support trending images, see [Trending Images](https://docs.microsoft.com/en-us/azure/cognitive-services/bing-image-search/trending-images).
  
  @param trendingOptionalParameter the object representing the optional parameters to be set before calling this API
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the TrendingImages object