/// <summary>
 /// Week before
 /// </summary>
 /// <param name="ld"></param>
 /// <returns></returns>
 public static LocalDate WeekBefore(this LocalDate ld) => ld.AddWeeks(-1);
 /// <summary>
 /// Week after
 /// </summary>
 /// <param name="ld"></param>
 /// <returns></returns>
 public static LocalDate WeekAfter(this LocalDate ld) => ld.AddWeeks(1);