Q: 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 am Lisa Adams. 
 agent:  How can I aid you? 
 customer: I want to book a flight ticket from CA - SFO to FL - MCO to meet my cousin in Orlando. 
 agent: May I know your travelling dates? 
 customer: I will start on 12/24, return on 12/26. 
 agent: Do you have any preference? 
 customer: I need a halt in between my journey. 
 agent: Sorry, no flights are available on your travel dates. 
 customer: No problem, thank you. 
 agent:  Thank you for opting us.
A:
no_flight