export declare class DateHelper {
    private dayJsLibrary;
    /**
     * Creates or returns instance of the dayJs library
     * @returns instance of the dayJs library
     */
    dayJs(culture?: string): Promise<unknown>;
    private setLocale;
    isDST(): boolean;
    addMinutes(isDst: boolean, date: Date, minutes: number, dst: number): Date;
}