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, I am Gary Mitchell. 
 agent: Hello. How can I assist you today? 
 customer: I need to attend for an interview at LAX. Can you please help me to book a flight from PHL? 
 agent: Sure, can you please share your travel dates? 
 customer: Ok, my planned trip dates are Dec 8 - Dec 10. 
 agent: Do you have any class preference? 
 customer: Yes, I want to travel in economy class. 
 agent: Gary Mitchell, there is a flight available with price 100 and the connection is 1 with UA airline. Would you like me to proceed with the booking? 
 customer: Ok, please proceed. 
 agent: Your booking is confirmed with 1014 flight number. 
 customer: Thank you. 
 agent: You are welcome. Thank you for contacting us.
book