code: private static ImmutableMap<String, ImmutableWorkerInfo> getNonAffinityWorkers(
        final AffinityConfig affinityConfig,
        final Map<String, ImmutableWorkerInfo> workerMap
    )
    {
      return ImmutableMap.copyOf(
          Maps.filterKeys(
              workerMap,
              workerHost -> !affinityConfig.getAffinityWorkers().contains(workerHost)
          )
      );
    }
docs: Return workers not assigned to any affinity pool at all.
  
  @param affinityConfig affinity config
  @param workerMap      map of worker hostname to worker info
  
  @return map of worker hostname to worker info