Given the task definition and input, reply with output. 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 assist you now? 
 customer: I need to attend an interview in University of Texas at Austin, AUS. 
 agent: Ok. 
 customer: Can you please help in booking on 09/11 and 09/13? 
 agent: Sure, may I know your airport codes? 
 customer: My source point is Atlanta, ATL. 
 agent: Ok, do you need any connection limit? 
 customer: I need a halt in between journey. 
 agent: There is a flight found with Delta airline of flight number 1003 and fare is 100. Shall I proceed for booking? 
 customer: Yes you can proceed. 
 agent: To proceed further, I need to know your good name? 
 customer: Brandon Scott is my name. 
 agent: Your ticket has been confirmed. 
 customer: Thank you for your help. 
 agent: Thanks for choosing us.
book