static WordCountsResponse aggregateResponses(List<WordCountsResponse> responses){
  WordCountsResponse result=WordCountsResponse.fromWordCounts(new HashMap<>());
  responses.forEach(null);
  return result;
}

static WordCountsResponse aggregateResponses ( List < WordCountsResponse > responses ) { WordCountsResponse result = WordCountsResponse . fromWordCounts ( new HashMap < > ( ) ) ; responses . forEach ( null ) ; return result ; }
helper method to aggregate response by summing the word counts and the failures .
