gistfile1.txt

// Why write this..
public static <T, V> Map<T, List<V>> defaultdict_list() {
    return new MapMaker().makeComputingMap(new Function<T, List<V>>() {
        @Override public List<V> apply(T unusedCrap) {
            return Lists.newArrayList();
        }
    });
}

# When you just want this (Python)
defaultdict(list)

# Or this (Ruby)
Hash.new {|h,k| h[k] = []}