Q: 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 may I help you? 
 customer: I am Christopher Gonzalez. I want to travel from IAH to IAD. Can you book a flight ticket for me? 
 agent: Sure, I am here to help you. Could you please share your travelling dates? 
 customer: I want to fly on 05/02 and 05/04. 
 agent: Flight-1020 of Hawaiian airlines is available for you, shall I proceed? 
 customer: Proceed with booking. 
 agent: Ok, your ticket is booked. 
 customer: Thank you for your help. 
 agent: Welcome.
A:
book