Detailed Instructions: 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
Problem:customer: Hi, I am John Carter. 
 agent: Hello, how may I serve you? 
 customer: Can you please help me with booking a flight ticket from DCA to LAS? 
 agent: Sure, may I know your travelling dates? 
 customer: Travelling dates are 07/26 and 07/28. 
 agent: Do you need any stopover in between your journey? 
 customer: I need a single connection. 
 agent: There is a flight found with number 1000, Delta as airline and the cost of the ticket is 200. Shall I proceed? 
 customer: You can proceed with booking. 
 agent: Thanks for availing us. Your ticket is booked. 
 customer: Thanks for the help.
Solution:
book