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
One example is below.
Q: customer: Hi. 
 agent: Hello. How can I help you? 
 customer: I would like to change my existing reservation as my plan to go for a holiday trip got postponed. Can you please help me with this? 
 agent: Sure, may I know your name please? 
 customer: My name is Anthony Phillips. 
 agent: Please wait a moment. 
 customer: Sure. 
 agent: Unfortunately there is no reservation found with your given name. 
 customer: Not a problem, thank you for checking. 
 agent: Thank you for choosing us.
A: no_reservation
Rationale: Here the customer has not asked for any booking, he just wanted to update his already booked flight, so the status would be no_reservation
Q: customer: Hello. 
 agent: Hello. How may I assist you? 
 customer: My name is Raymond Phillips. I have a business meeting in Washington, can you help me for booking a flight ticket from IAD to IAD? 
 agent: Sure, I will help you. Can you please let me know your travel dates? 
 customer: My travelling dates are 01/28 and 01/30. 
 agent: Ok, please wait for a while. 
 customer: Make sure that my connection limit should be 1. 
 agent: As per your requirements, there is a flight available with Delta airlines and the ticket fare is 100 only. Shall I book the ticket for you? 
 customer: Ok, please proceed for booking. 
 agent: Phillips, your ticket is booked and your flight number is 1016. 
 customer: Thank you for booking. 
 agent: You are welcome and thank you for choosing us.
A:
book