function getCalendarWeekParameter (oFormatOptions) {
		if (oFormatOptions.calendarWeekNumbering) {
			return oFormatOptions.calendarWeekNumbering;
		// either both are provided or none (checked in DateFormat.createInstance)
		} else if (oFormatOptions.firstDayOfWeek !== undefined && oFormatOptions.minimalDaysInFirstWeek !== undefined) {
			return {
				firstDayOfWeek: oFormatOptions.firstDayOfWeek,
				minimalDaysInFirstWeek: oFormatOptions.minimalDaysInFirstWeek
			};
		}
		return undefined;
	}
Retrieves the parameter for the calendar week configuration from the DateFormat's format
options

@param {{firstDayOfWeek: int, minimalDaysInFirstWeek: int, calendarWeekNumbering: module:sap/base/i18n/date/CalendarWeekNumbering}} oFormatOptions
  The format options with which the DateFormat instance was created
@returns {module:sap/base/i18n/date/CalendarWeekNumbering|{firstDayOfWeek: int, minimalDaysInFirstWeek: int}|undefined}
  The parameter for the calendar week configuration