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
Input: customer: Hello. 
 agent: Hello, how can I assist you today? 
 customer: I want to attend a Seminar in Washington. Can you please help me for booking the flight ticket? 
 agent: Sure, Can you please provide your take off and landing airport codes? 
 customer: My airport codes are LAS and IAD. 
 agent: On which dates would you like me to book a flight ticket for you? 
 customer: My travelling dates are June 17 and June 19. 
 agent: On what name, do I need to reserve your ticket? 
 customer: Ashley Walker. 
 agent: Let me know your connection limit? 
 customer: I prefer single connecting flight. 
 agent: Do you have any other requirements? 
 customer: No. 
 agent: Sorry to inform you, currently no flights are running at that locations due to abnormal weather conditions. 
 customer: Anyway, thanks for the information. 
 agent: Thank you for choosing us.
Output:
no_flight