/**
 * Checks if the given object is a valid date object.
 *
 * @param {any} dateObj The object to check.
 * @returns {boolean} True if the object is a valid date object, false otherwise.
 *
 * Example:
 * ```ts
 * console.log(DateHelper.DateHelper.isDateObj(new Date())); // Output: true
 * console.log(DateHelper.DateHelper.isDateObj({})); // Output: false
 * console.log(DateHelper.DateHelper.isDateObj("2022-01-01")); // Output: false
 * ```
 */
export declare function isDateObj(dateObj: any): dateObj is Date;