class BidirectionalTracerouteAnswerer extends Answerer {

  @VisibleForTesting
  static Map<BidirectionalTrace.Key, List<BidirectionalTrace>> groupTraces(
      List<BidirectionalTrace> traces) {
    return traces.stream()
        .collect(Collectors.groupingBy(BidirectionalTrace::getKey, Collectors.toList()));
  }

  public  BidirectionalTracerouteAnswerer(Question question, IBatfish batfish);

}