code: public static <K, V> Function<Map.Entry<K, V>, V> entryToValueFunction() {
        return EntryToValueFunction.getInstance();
     }
docs: Provides a function that returns the value of the entry when invoked.
  @param <K> key type of the entry
  @param <V> value type of the entry
  @return a function that when applied to a given entry will return the value