Detailed 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
Q: customer: Hi. 
 agent: Hello. How can I help you? 
 customer: I am Jason Young. Can you help me to book a flight on 01/30 and 02/01? 
 agent: Sure, I will help you to book a flight. Can you please provide me your travelling airport codes? 
 customer: My preferred airport codes are IAD and AUS. 
 agent: There is one flight is available for you with single connection. Shall I proceed for booking? 
 customer: Yes, proceed. 
 agent: Your ticket is booked with flight number 1000 and airline is Spirit. 
 customer: Thank you for your help. 
 agent: Welcome.
A:
book