Instructions: In this task, you are given a conversation between a flight agent and the customer. You are given 4 options and you need to select the goal of the conversation. It is provided as part of customer's context, which has to be one of the following: `book`: Make a new reservation, `cancel`: Cancel an existing reservation, `no_flight`: No flight found for the customer's preference, `no_reservation`: No reservation / No change / No cancellation was made in the conversation, mostly enquiring details
Input: customer: Hello. 
 agent: Hello, how may I guide you today? 
 customer: I am Stephen Turner, can you assist me to book a flight from DEN to ATL? 
 agent: Sure, could you please share me with your dates of trip? 
 customer: Ok, my travel date is on 01/07 from Denver and return date is on 01/09. 
 agent: Ok, please hold on for a mean while. The flight with the connecting flight of fare 100 has found, shall I book this ticket booking? 
 customer: Ok, please the book. 
 agent: The flight with the Delta airline and flight number is 1009 has been confirmed. 
 customer: Thank you for helping me with the booking. 
 agent: You are welcome and have a happy journey.
Output:
book