public function getHolidaysForMonth($year, $month, $region, DateTimeZone $timezone = null)
    {
        $holidayList = $this->holidayCalculator->calculateHolidaysForYear($year, $region, $timezone);
        $date = new DateTime(sprintf('%s-%s-01', $year, $month), $timezone);
        $lastDayOfMonth = (int) $date->format('t');
        $filteredHolidays = (new IncludeTimespanFilter())->filter($holidayList, [
            IncludeTimespanFilter::PARAM_FIRST_DAY => $date,
            IncludeTimespanFilter::PARAM_LAST_DAY => new DateTime(sprintf('%s-%s-%s', $year, $month, $lastDayOfMonth), $timezone),
        ]);

        return $filteredHolidays;
    }