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. 
 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.
book