code: public Observable<Void> deleteImageRegionsAsync(UUID projectId, List<String> regionIds) {
          return deleteImageRegionsWithServiceResponseAsync(projectId, regionIds).map(new Func1<ServiceResponse<Void>, Void>() {
              @Override
              public Void call(ServiceResponse<Void> response) {
                  return response.body();
              }
          });
      }
docs: Delete a set of image regions.
  
  @param projectId The project id
  @param regionIds Regions to delete. Limited to 64
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the {@link ServiceResponse} object if successful.