You will be given a definition of a task first, then some input of the task.
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

customer: Hello. 
 agent: Hello, How can I serve you? 
 customer: I would like to travel from Detroit, DTW to Las Vegas, LAS as a holiday trip. Can you do the reservation? 
 agent: Sure. May I know your travelling dates? 
 customer: Dates are 08/29 and 08/31. 
 agent: May I know your good name? 
 customer: Ronald Walker here. 
 agent: There is a flight 1023 in Delta airline and price 100 with a connection. Shall I proceed? 
 customer: Go ahead. 
 agent: Ok, Your ticket is done. 
 customer: Thank you so much. 
 agent: Thank you.
Output:
book