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: Hello. 
 agent: Hello. How can I assist you? 
 customer: Is this Travel leaders agency? 
 agent: Yes. 
 customer: I am Ruth Campbell, I am planning to travel from Houston to Denver to meet my friends after a long time. 
 agent: Sure, I will help you to travel. May I know your airport codes? 
 customer: I am departing from HOU and my destination airport is DEN. 
 agent: Ok, can you please provide me your travelling dates? 
 customer: My departure from Houston is on 09/06 and return from Denver on 09/08. 
 agent: I am happy to say you this, I found a flight for you with 1 connection. Shall I proceed for booking? 
 customer: Yes, please proceed for booking. 
 agent: Your ticket is reserved with flight number 1003 and airline is Southwest. 
 customer: Thanks for your assistance. 
 agent: Thank you for choosing us. Welcome.
A:
book