Teacher: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
Teacher: Now, understand the problem? Solve this instance: customer: Hello. 
 agent: Hello. How can I help you? 
 customer: Mark Evans here. I want to attend my Nephew's marriage in Charlotte.Can you please help me for booking a ticket? 
 agent: Yes, could you tell me your travelling dates? 
 customer: My departure date is 12/24 and return date is 12/26. 
 agent: Ok. Can you share your travelling airport codes? 
 customer: My airport codes are from NY-LGA to NC-CLT. Make sure my connections limit is 1. 
 agent: Give me a moment, I will get back to you. 
 customer: Ok. 
 agent: I have found a flight or you with a price of 100. Can I book the ticket? 
 customer: Please proceed for booking. 
 agent: Your ticket is booked. 
 customer: Thank you for helping me. 
 agent: The flight number is 1012 of UA airlines. You are welcome.
Student:
book