Q: 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
customer: Hello. 
 agent: Hello, how may I help you? 
 customer: I am Catherine Clark from Detroit. I want to make a reservation from LGA to DTW. Can you please help me with this? 
 agent: Sure, when are you planning to travel? 
 customer: Thank you, my travelling dates are Nov 16 - Nov 18. 
 agent: Do you need any stopover? 
 customer: No, I need a direct flight. 
 agent: Thanks for the information, please stand by. 
 customer: Sure. 
 agent: There is no flight available on mentioned dates. 
 customer: Ok, no problem. Thank you for the information. 
 agent: Thank you.
A:
no_flight