i need to find a train from cambridge .
user
there are trains leaving cambridge every 2 hour -s .
assistant
i need 1 on friday heading to ely . i need to leave after 19:30 .
user
the train closest to your desired time is tr6053 which departs cambridge at 19:50 and arrives in ely at 20:07 . would you like to book a ticket ?
assistant
what is the travel time on that train ?