generate response: i want to leave the hotel by 4:30. Intent: book_hotel. Slots: taxi-departure=cambridge belfry, taxi-destination=milton country park, taxi-leaveat=04:30, 4:30, hotel-area=west, hotel-bookday=friday, hotel-bookpeople=5, hotel-bookstay=4, hotel-name=cambridge belfry, hotel-pricerange=cheap, hotel-stars=4, hotel-type=hotel
Response: What time do you need to leave the restaurant by?