Given the task definition and input, reply with output. 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. 
 customer: I want to visit TX-DFW to see the Sixth Floor Museum at Dealey Plaza, can you help me to make a flight reservation? 
 agent: Sure, please share your planned dates. 
 customer: My preferable travel dates are 02/15 and 02/16. 
 agent: May I know your source airport code? 
 customer: Currently I am staying in WA-SEA. Once check my return date will be on 02/17. 
 agent: Please give me a moment. 
 customer: Sure. 
 agent: Delta airlines with flight 1019 is available for you. 
 customer: May I know the connection limit? 
 agent: It's a direct flight. 
 customer: But, I need flight with 1 connection. 
 agent: May I know your name? 
 customer: Can you once search with this connection. I am Gary Lopez. 
 agent: Please wait for a while. 
 customer: Sure, please take your own time. 
 agent: Sorry, we could not find a flight with 1 connection. 
 customer: It's not a problem. 
 agent: Thank you for approaching us. 
 customer: Thank you for your valuable information.
no_flight