code: public static <K, V> Func1<Iterable<Pair<K, V>>, SolidMap<K, V>> pairsToSolidMap() {
          return new Func1<Iterable<Pair<K, V>>, SolidMap<K, V>>() {
              @Override
              public SolidMap<K, V> call(Iterable<Pair<K, V>> iterable) {
                  return new SolidMap<>(iterable);
              }
          };
      }
docs: Returns a function that converts a stream of {@link Pair} into {@link SolidMap}.