docs: @VisibleForTesting
    FeedPartition findPartitionToProcess(List<WorkerStatus> workerStatus, List<FeedPartition> feedPartitions){
      for (int i = 0; i < feedPartitions.size(); i++) {
        FeedPartition aPartition = feedPartitions.get(i);
        boolean partitionTaken = false;
        for (int j = 0; j < workerStatus.size(); j++) {
          if (workerStatus.get(j).getFeedPartitionId().equals(aPartition.getPartitionId())) {
            partitionTaken = true;
          }
        }
        if (partitionTaken == false){
          return aPartition;
        }
      }
      return null;
    }