You will be given a definition of a task first, then some input of the task.
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 Joshua Martinez. I want to book a flight from PHX to reach MSP to meet my high school friends. Can you book a connecting flight for me? 
 agent: Sure, may I know your journey dates? 
 customer: I have planned to travel on July 2nd and return on July 4th. 
 agent: Do you need a economy class? 
 customer: No. 
 agent: Can I know your requirements? 
 customer: I would like to depart at evening time. 
 agent: Ok, wait a minute. 
 customer: Ok. 
 agent: Sorry, there are no flights available. 
 customer: Ok, no problem. Thank you. 
 agent: Thank you for choosing us.
Output:
no_flight