code: public Map<Integer, Hour> getHours(DayOfWeek day) {
      if (hours.get(day) == null) {
        return null;
      }
  
      return Collections.unmodifiableMap(hours.get(day));
    }
docs: Returns a map of indices and {@link Hour} objects with the open and close time
  
  @param day
  the day the map should be returned for
  @return the map containing the index and the {@link Hour} object