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: Hello. 
 agent: Hello, how may I help you today? 
 customer: I need to travel Las Vegas, can you please reserve normal-cost flight ticket from PHL and LAS? 
 agent: Sure, may I know your planned travel dates? 
 customer: My travelling dates are Dec,18 and Dec,20. 
 agent: Do you have any limits on number of connections? 
 customer: I need a single connection for my travel. 
 agent: Thank you, may I know your name for the documentation purpose? 
 customer: Myself Joshua Brown and I need a business class flight ticket. 
 agent: Do you have any specific depart and arrival time for this journey? 
 customer: No, I have mentioned all my specification. 
 agent: Thank you, please wait for a moment. 
 customer: Sure, please take your time. 
 agent: Unfortunately, no flights are available on your requirement dates. 
 customer: That's ok, I will choose any other alternate source to reach my destination. 
 agent: Welcome, thank you for reaching us.
Solution:
no_flight