generate response: I want to depart from London Liverpool Street after 15:00.. Intent: find_train. Slots: train-day=sunday, train-departure=london liverpool street, train-destination=cambridge, train-leaveat=15:00
Response: There is a train leaving on that date from london liverpool to cambridge at 15:39, arrive at 17:07 with a price of 13.28 pounds. Would you like to book?