How to use the @ui5/webcomponents-base/dist/dates/CalendarDate.js function in @ui5/webcomponents-base

const iFirstDayOfWeek = this._getFirstDayOfWeek();

		// determine weekday of first day in month
		const oFirstDay = new CalendarDate(oStartDate, this._primaryCalendarType);
		oFirstDay.setDate(1);
		iDaysOldMonth = oFirstDay.getDay() - iFirstDayOfWeek;
		if (iDaysOldMonth < 0) {
			iDaysOldMonth = 7 + iDaysOldMonth;
		}

		if (iDaysOldMonth > 0) {
			// determine first day for display
			oFirstDay.setDate(1 - iDaysOldMonth);
		}

		const oDay = new CalendarDate(oFirstDay);
		for (let i = 0; i < 42; i++) {
			iYear = oDay.getYear();
			oCalDate = new CalendarDate(oDay, this._primaryCalendarType);
			if (bIncludeBCDates && iYear < MIN_YEAR) {
				// For dates before 0001-01-01 we should render only empty squares to keep
				// the month square matrix correct.
				oCalDate._bBeforeFirstYear = true;
				_aVisibleDays.push(oCalDate);
			} else if (iYear >= MIN_YEAR && iYear <= MAX_YEAR) {
				// Days before 0001-01-01 or after 9999-12-31 should not be rendered.
				_aVisibleDays.push(oCalDate);
			}
			oDay.setDate(oDay.getDate() + 1);
		}

		return _aVisibleDays;

const oFirstDay = new CalendarDate(oStartDate, this._primaryCalendarType);
		oFirstDay.setDate(1);
		iDaysOldMonth = oFirstDay.getDay() - iFirstDayOfWeek;
		if (iDaysOldMonth < 0) {
			iDaysOldMonth = 7 + iDaysOldMonth;
		}

		if (iDaysOldMonth > 0) {
			// determine first day for display
			oFirstDay.setDate(1 - iDaysOldMonth);
		}

		const oDay = new CalendarDate(oFirstDay);
		for (let i = 0; i < 42; i++) {
			iYear = oDay.getYear();
			oCalDate = new CalendarDate(oDay, this._primaryCalendarType);
			if (bIncludeBCDates && iYear < MIN_YEAR) {
				// For dates before 0001-01-01 we should render only empty squares to keep
				// the month square matrix correct.
				oCalDate._bBeforeFirstYear = true;
				_aVisibleDays.push(oCalDate);
			} else if (iYear >= MIN_YEAR && iYear <= MAX_YEAR) {
				// Days before 0001-01-01 or after 9999-12-31 should not be rendered.
				_aVisibleDays.push(oCalDate);
			}
			oDay.setDate(oDay.getDate() + 1);
		}

		return _aVisibleDays;
	}

_getVisibleDays(oStartDate, bIncludeBCDates) {
		let oCalDate,
			iDaysOldMonth,
			iYear;

		const _aVisibleDays = [];

		// If date passed generate days for new start date else return the current one
		if (!oStartDate) {
			return _aVisibleDays;
		}

		const iFirstDayOfWeek = this._getFirstDayOfWeek();

		// determine weekday of first day in month
		const oFirstDay = new CalendarDate(oStartDate, this._primaryCalendarType);
		oFirstDay.setDate(1);
		iDaysOldMonth = oFirstDay.getDay() - iFirstDayOfWeek;
		if (iDaysOldMonth < 0) {
			iDaysOldMonth = 7 + iDaysOldMonth;
		}

		if (iDaysOldMonth > 0) {
			// determine first day for display
			oFirstDay.setDate(1 - iDaysOldMonth);
		}

		const oDay = new CalendarDate(oFirstDay);
		for (let i = 0; i < 42; i++) {
			iYear = oDay.getYear();
			oCalDate = new CalendarDate(oDay, this._primaryCalendarType);
			if (bIncludeBCDates && iYear < MIN_YEAR) {