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 can I aid you at this moment? 
 customer: Can you please help me to book a ticket from SEA to PHX? 
 agent: Sure, I will help you with this. Can you please provide your journey dates? 
 customer: My journey dates are on July 19 and July 21. 
 agent: Do you have any connection limit preference. 
 customer: I need single stopover. 
 agent: Do you have any other specifications? 
 customer: No. 
 agent: May I know your good name please? 
 customer: My name is Rachel Young. 
 agent: United Airlines is providing connecting flight on this route with a ticket fare of 100 and flight departs at 15:00PM and arrives at 2:00AM, shall I book your ticket in this flight? 
 customer: You can proceed. 
 agent: Rachel Young, your ticket is booked in economy class of flight number 1011. 
 customer: Thank you. 
 agent: You are welcome and have a safe journey.
Output:
book