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

Example Input: customer: Hello. 
 agent: Hello, how may I render you today? 
 customer: I need your help to book a flight from IAD to DCA. 
 agent: Sure, we are here to help you. Please let me know your connection limit? 
 customer: Thank you. I am looking for a flight with single connection. 
 agent: May I know your good name? 
 customer: Myself Sarah Hall. 
 agent: Could you please share your journey dates? 
 customer: Sure, I want to travel on Apr 26 and need to return on Apr 28. 
 agent: Are there any more specifications? 
 customer: My depart time must be in the evening. 
 agent: We found a connecting flight 1007 from Hawaiian airline has fare 100 and departure time is 2:00 hours. 
 customer: Ok, please proceed. 
 agent: Your booking has been processed. 
 customer: Thank you. 
 agent: Thank you for choosing us.
Example Output: book

Example Input: customer: Hi. I am Jessica Evens. 
 agent: Hello,. How may I serve you? 
 customer: I want to book a flight ticket on  01/04 to 01/06 for which I have a exam at IAH. 
 agent: Sure, may I know your origin point? 
 customer: My source code is ATL. And I want with 1 connection. 
 agent: Sorry to inform that there is no flight found with your specification. 
 customer: Ok. Thank you for  information and your service. 
 agent: Thank you for reaching us.
Example Output: no_flight

Example Input: customer: Hi, myself Jack Thomas. 
 agent: Hello Jack, how may I help you? 
 customer: I need your help in booking my flight ticket from ATL to IAD, can you please help me? 
 agent: Sure, I can help you. May I know your journey dates? 
 customer: Sure, I would like to depart on 01/17 and return on 01/19. 
 agent: Please give me a moment. 
 customer: Sure. 
 agent: Spirit airlines with flight 1015 is available on your route. 
 customer: That's fine for my journey, you can proceed for booking the ticket. 
 agent: Your ticket is reserved. 
 customer: Thank you very much for your help. 
 agent: Thank you for choosing us.
Example Output:
book