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: Hi, I am John Nelson. 
 agent: Hello, what kind of assistance you are looking for? 
 customer: Can you please help me with booking a flight ticket from LAX to IAD? 
 agent: Sure, I am ecstatic to help you. 
 customer: Thank you. 
 agent: Let me know, how much you can afford for this journey? 
 customer: I can afford up to 5000. 
 agent: Do you have any class preference? 
 customer: I prefer business class. 
 agent: Kindly, share your travelling dates to proceed further. 
 customer: Travel dates are 12/06 and 12/08. 
 agent: Thank you for sharing your details. Please, hold on for a while. 
 customer: Ok. 
 agent: Thank you for waiting, there are no flights available with your requirements. 
 customer: Ok, no issues. Thanks for the help. 
 agent: Thank you for approaching us.
Student:
no_flight