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: Hi, I am Donna Baker. 
 agent: Hello, how may I assist you Donna Baker? 
 customer: I want to meet my friend at Central Park in New York, can you please book me a direct fight? 
 agent: Sure, we will book a ticket. Help me with your journey dates. 
 customer: My trip dates are from 05/05 to 05/07. 
 agent: Ok, let me know your locations. 
 customer: My airport codes are from Boston, MA-BOS to New York, NY-LGA. 
 agent: Ok, please wait. 
 customer: Ok]. 
 agent: Thank you for waiting, no flights were found based on your schedule. 
 customer: Ok, no issues. Thank you for your response. 
 agent: Thank you for picking us.
Output:
no_flight