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 help you? 
 customer: Can you please help me in booking a flight ticket from Denver, DEN to Phoenix, PHX? 
 agent: Sure, help me with the trip dates? 
 customer: My journey dates are from Aug 15 to Aug 17. 
 agent: Do you have any specifications to be met? 
 customer: No. 
 agent: May I know your name for the documentation purpose? 
 customer: My name is Kevin Harris. 
 agent: We found a flight in an airline Hawaiian with 1026 number having a single connection in an economy class. Shall I proceed to book? 
 customer: Sure, you can proceed for booking. 
 agent: Your flight ticket has been confirmed. 
 customer: Thanks for your help. 
 agent: Thank you for opting us.
Example Output: book

Example Input: customer: Hello. 
 agent: Hello, how can I aid you? 
 customer: I am Stephen Adams. Can you please help me to change my reservation? 
 agent: Sure, please wait. 
 customer: Ok. 
 agent: There is no reservation found with your name. 
 customer: Ok, no problem. Thank you. 
 agent: Have a good day.
Example Output: no_reservation

Example Input: customer: Hello,. 
 agent: Hello. 
 customer: Can you please help me in changing my existing reservation, as my exam got postponed. 
 agent: Sure, I will help you. 
 customer: Thank you. 
 agent: May I know your good name to check your reservation status? 
 customer: I am William Thompson. 
 agent: Ok, please be on hold. I will check your reservation status and get back to you soon. 
 customer: Ok. 
 agent: Sorry, we have found no reservation on your name in our records. 
 customer: Ok, no issues,. Thank you for your information. 
 agent: Thank you for reaching us.
Example Output:
no_reservation