def save_seat(cls, user_id, projection_id, row, col):
if UserController.check_id(user_id) is False:
raise UserError('There is no user with id = {}!'.format(user_id))
if ProjectionController.check_id(projection_id) is False:
raise ProjectionException(
'There is no projection with id = {}!'.format(projection_id))
if cls.check_if_seat_is_taken(projection_id, row, col):
raise SeatError('The seat is taken!')
session.add(
Reservation(user_id=user_id,
projection_id=projection_id,
row=row,
col=col))
