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. 
 customer: I am Jack Clark. 
 agent: How can I assist you today? 
 customer: I need to attend a wedding in New York. Can you help me to book a ticket from AUS to EWR? 
 agent: Sure, can you please share your preferable travel dates? 
 customer: I would like to travel on 08/12 and 08/14. 
 agent: Ok, let me check for the availability of flight on this route. 
 customer: Sure, take your time. 
 agent: Jack, I am sorry to inform you that there is no flight available at your request. 
 customer: That's ok. Anyways, thank you for your help. 
 agent: You are welcome. Thank you for contacting us.
Output:
no_flight