static public string Insert_Schedule(Schedule aSchedule)
 {
     if (ScheduleGateway.Check_Schedule(aSchedule))
     {
         return("\n\tSorry, this Schedule is aleady booked ."
                + "\n\tEnter Another one .");
     }
     if (ScheduleGateway.Insert_Into_Database(aSchedule) >= 1)
     {
         return("\n\tYour Schedule is saved .");
     }
     return("\n\tCan not save schedule .");
 }