anchor.diff:      .then((response) {
         var results = response.map((world) {
           return {
  -          "id": world["id"],
  -          "randomnumber": world["randomnumber"]
  +          "id": world["_id"],
  +          "randomNumber": world["randomNumber"]
           };
         });
         connect.response.write(json.stringify(results.toList()));
  
positive.code:   
    return _mongoQuery().then((data) {
      connect.response.write(json.stringify({
        "id": data["id"],
        "randomnumber": data["randomnumber"]
      }));
    });
  }
  
negative.code:     .then((worlds) {
        var result = worlds.map((world) {
          return {
            "id": world["_id"],
            "randomNumber": world["randomNumber"]
          };
        });
        connect.response.write(json.stringify(result.toList()));
  