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: Hi, Dorothy Collins here. 
 agent: Hello, how can I be your helping hand? 
 customer: I would like to visit Puget sound at Seattle, WA - SEA. Can you please book a ticket from AUS? 
 agent: Sure, can I know your travel dates? 
 customer: My trip dates are 11/08 and 11/10. 
 agent: We found a flight on southwest airline, flight number 1011 with the fare of 100. 
 customer: Please book this. 
 agent: Your ticket has been booked. 
 customer: Thank you for assisting me. 
 agent: Thank you for choosing us.
book