code: public static <T1, T2, T3, T4, T5, T6, T7, T8, T9> Func9<T1, T2, T3, T4, T5, T6, T7, T8, T9, Void> toFunc(
              final Action9<T1, T2, T3, T4, T5, T6, T7, T8, T9> action) {
          return toFunc(action, (Void) null);
      }
docs: Converts an {@link Action9} to a function that calls the action and returns {@code null}.
  
  @param action the {@link Action9} to convert
  @return a {@link Func9} that calls {@code action} and returns {@code null}