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, how may I serve you today? 
 customer: Pamela Perez here, looking for a flight with single connection to go WA-SEA for my music concert. Can you please help me in booking? 
 agent: Sure, we are happy to help you. 
 customer: Thank you. 
 agent: May I know your price limit? 
 customer: I can spend up to 500. 
 agent: Please provide your origin point? 
 customer: It's DC-DCA. 
 agent: When would like to return on? 
 customer: I would like to return on 07/10. 
 agent: Thank you for your details there are no matching flights available with the given details. 
 customer: OK, not an issue. 
 agent: Thank you for opting us, have a great day. 
 customer: Thank you.
Output:
no_flight