code: public Observable<IterationPerformance> getIterationPerformanceAsync(UUID projectId, UUID iterationId, GetIterationPerformanceOptionalParameter getIterationPerformanceOptionalParameter) {
          return getIterationPerformanceWithServiceResponseAsync(projectId, iterationId, getIterationPerformanceOptionalParameter).map(new Func1<ServiceResponse<IterationPerformance>, IterationPerformance>() {
              @Override
              public IterationPerformance call(ServiceResponse<IterationPerformance> response) {
                  return response.body();
              }
          });
      }
docs: Get detailed performance information about an iteration.
  
  @param projectId The id of the project the iteration belongs to
  @param iterationId The id of the iteration to get
  @param getIterationPerformanceOptionalParameter 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 IterationPerformance object