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, I am Dorothy Brown. 
 agent: Hello, how may I provide assistance to you? 
 customer: I am planning to visit downtown aquarium at Denver CO - DEN, can you please book a flight from DTW? 
 agent: Sure, I am ravish to help you. Can you please help me with providing your journey dates? 
 customer: My journey dates are 05/13 to 05/15. 
 agent: May I know at what price you are looking for airfare? 
 customer: My affordable price is 5000. 
 agent: Do you prefer any halt in between journey? 
 customer: I need a halt. 
 agent: We found a connecting flight with Frontier airlines, flight number 1014 and the fare of 200. Shall I proceed? 
 customer: Yes, please proceed. 
 agent: Your ticket has been reserved in economy class. 
 customer: Thank you for your help. 
 agent: Thank you for approaching us.
Output:
book