docs: public List<ModelServiceInstance> queryUPModelInstances(ServiceInstanceQuery query){
          List<ModelServiceInstance> upInstances= null;
          List<ModelServiceInstance> instances = queryModelInstances(query);
          if(instances != null && instances.size() > 0){
  
              for(ModelServiceInstance instance : instances){
                  if(OperationalStatus.UP.equals(instance.getStatus())){
                      if(upInstances == null){
                          upInstances = new ArrayList<ModelServiceInstance>();
                      }
                      upInstances.add(instance);
                  }
              }
          }
          if(upInstances == null){
              return Collections.emptyList();
          }
          return upInstances;
  
      }