code: public Observable<List<UsageInner>> listByLocationAsync(String location) {
          return listByLocationWithServiceResponseAsync(location).map(new Func1<ServiceResponse<List<UsageInner>>, List<UsageInner>>() {
              @Override
              public List<UsageInner> call(ServiceResponse<List<UsageInner>> response) {
                  return response.body();
              }
          });
      }
docs: Gets the current usage count and the limit for the resources of the location under the subscription.
  
  @param location The location of the Azure Storage resource.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the List&lt;UsageInner&gt; object