generate response: I am departing from Cambridge and would like to be in Birmingham New Street by 20:45 at the latest.. Intent: find_train. Slots: train-arriveby=20:45, train-day=saturday, train-departure=cambridge, train-destination=birmingham new street
Response: The earliest train available is train TR4975 which departs at 5:01 and arrives at 7:44. Can I book that for you?