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 can I assist you? 
 customer: I am planning to book a flight ticket to DCA from OAK, can you please help me out? 
 agent: Sure, I can help you with that. May I know your travel dates please? 
 customer: Sure, my planned travelling dates are May 24 and May 26. 
 agent: May I know how many connections are you expecting in between your journey? 
 customer: Sure, I am looking for a flight with 1 connection. 
 agent: Please let me know if you have any other specifications. 
 customer: That's all for now. 
 agent: Can I have your good name please? 
 customer: Sure, my name is Jason Young. 
 agent: JetBlue airlines is providing a flight on that route with ticket fare of 100 and single connection, it will departs at 12:00 hours and arrives at 5:00 hours. Shall I proceed for booking? 
 customer: Ok, please confirm my reservation. 
 agent: I have successfully booked you an economy class ticket in flight-1014, have a safe journey. 
 customer: Thank you for the help. 
 agent: Thank you for choosing us.
Example Output: book

Example Input: customer: Hello. 
 agent: Hello. 
 customer: I am Christopher Taylor. 
 agent: How can I help you? 
 customer: I planned to meet my cousin in DCA, can you please help me to book a flight ticket from PHL? 
 agent: Sure, can you please tell your travelling dates? 
 customer: I planned to travel on 02/18 and 02/20. 
 agent: Sorry, there are no flights available with your requested details. 
 customer: Ok, no problem. Thank you for your time. 
 agent: Thank you and have a nice day.
Example Output: no_flight

Example Input: customer: Hello. 
 agent: Hello. How may I help you? 
 customer: Can you please check the availability of flights in between the points Washington and Boston? 
 agent: Sure, may I know you trip dates? 
 customer: I will depart on 08/10 and return on 08/12. 
 agent: Help me with the airport codes? 
 customer: Sure, my source airport code is DC - IAD and destination airport code is MA - BOS. 
 agent: May I know your name please? 
 customer: Sure, I am Deborah Phillips. 
 agent: We found a flight in an airline Southwest with 1020 number having a single connection price of 100. Shall I reserve? 
 customer: Ok, please proceed for booking. 
 agent: Your flight ticket has been processed. 
 customer: Thank you. 
 agent: Thank you.
Example Output:
book