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: Hi. 
 agent: Hello. How may I assist you? 
 customer: I am looking for a direct flight from JFK to DTW, can you please help me to book my flight ticket? 
 agent: Sure, I am here to help you out. May I know your travelling dates please? 
 customer: Sure, I will depart on Jan 5th and I want to return back on Jan 7th. 
 agent: How much you can afford for airfare? 
 customer: I can only afford 500. 
 agent: Wait a moment please. 
 customer: Sure. 
 agent: May I know your name pleas to proceed further? 
 customer: Sure, my name is Catherine Mitchell. 
 agent: Catherine Mitchell, there are no flights available in you route. 
 customer: Not an issue, I will find an other way to reach my destination. Anyway, thank you. 
 agent: Thank you for choosing us.
no_flight