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,. I am Sharon Wright. 
 agent: Hello, how may I aid you for the day? 
 customer: I want to book a flight ticket to attend Sport's Festival in Houston, TX - IAH. Can you please help me in booking a flight ticket under the fare of 200? 
 agent: Sure, we are happy to help you. 
 customer: Thank you. 
 agent: May I know your source point? 
 customer: My origin airport code is Houston, TX - HOU. 
 agent: Ok, let me know your journey dates. 
 customer: I am willing to travel on 12/17 and intend to return on 12/19. 
 agent: Ok, please wait for sometime. 
 customer: Sure. 
 agent: Thanks for your time, no flights were found based on your schedule. 
 customer: Ok, no problem. Thank you. 
 agent: Thanks for choosing us.
no_flight