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. 
 customer: Laura Turner here. 
 agent: How may I aid you? 
 customer: Can you book a flight ticket for my airport codes that is from IAH to IAD? 
 agent: Ok, please mention your dates of travel. 
 customer: The travel dates are from Jan 03 to Jan 05. 
 agent: Do you have any other requirements? 
 customer: I would like to prefer a flight with a stopover option. 
 agent: There is a connecting flight-1009 in economy class, is it fine for you? 
 customer: You can book the flight ticket. 
 agent: Ok, booking is done on Delta airlines. 
 customer: Thank you. 
 agent: Welcome.
book