def update():
     if (len(CusID.get()) != 0):
         hotelDatabase.deleteRec(hd[0])
     if (len(CusID.get()) != 0):
         hotelDatabase.addHotelRec(CusID.get(), Firstname.get(),
                                   Surname.get(), Gender.get(),
                                   Address.get(), Mobile.get(),
                                   Nationality.get(), DateIn.get(),
                                   DateOut.get(), TotalCost.get())
         lstHotel.delete(0, END)
         lstHotel.insert(
             END,
             (CusID.get(), Firstname.get(), Surname.get(), Gender.get(),
              Address.get(), Mobile.get(), Nationality.get(),
              DateIn.get(), DateOut.get(), TotalCost.get()))
 def DeleteData():
     if (len(CusID.get()) != 0):
         hotelDatabase.deleteRec(hd[0])
         Reset()
         DisplayData()