code: public Observable<TagValueInner> createOrUpdateValueAsync(String tagName, String tagValue) {
          return createOrUpdateValueWithServiceResponseAsync(tagName, tagValue).map(new Func1<ServiceResponse<TagValueInner>, TagValueInner>() {
              @Override
              public TagValueInner call(ServiceResponse<TagValueInner> response) {
                  return response.body();
              }
          });
      }
docs: Creates a tag value. The name of the tag must already exist.
  
  @param tagName The name of the tag.
  @param tagValue The value of the tag to create.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the TagValueInner object