code: @SuppressWarnings("unchecked")
      public static <T> List<T> xor(final List<T> ... lists) {
          int index = -1;
          int length = lists.length;
          List<T> result = null;
          while (++index < length) {
              final List<T> array = lists[index];
              result = result == null ? array : concat(difference(result, array), difference(array, result));
          }
          return uniq(result);
      }
docs: /*
  _.xor([1, 2], [4, 2]);
  => [1, 4]