generate response: I want to leave Cambridge on Tuesday, after 21:30.. Intent: find_train. Slots: train-day=tuesday, train-departure=cambridge, train-destination=stevenage, train-leaveat=21:30
Response: TR3300 Departs from Cambridge on Tuesday at 23:21 and arrives in Stevenage by 24:10. The price is 12.80 pounds per ticket. Would you like me to book this for you?