docs: public Map<String, OperationResult<ModelService>> getChangedServices(Map<String, ModelService> services){
          String body = _serialize(services);
          HttpResponse result = invoker.invoke("/service/changing" , body, HttpMethod.POST);
  
          if (result.getHttpCode() != HTTP_OK) {
              throw new ServiceException(ErrorCode.REMOTE_DIRECTORY_SERVER_ERROR,
                      "HTTP Code is not OK, code=%s", result.getHttpCode());
          }
  
          Map<String, OperationResult<ModelService>> changedServices = _deserialize(
                      result.getRetBody(), new TypeReference<Map<String, OperationResult<ModelService>>>(){});
  
          return changedServices;
      }