Teacher: 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
Teacher: Now, understand the problem? If you are still confused, see the following example:
customer: Hi. 
 agent: Hello. How can I help you? 
 customer: I would like to change my existing reservation as my plan to go for a holiday trip got postponed. Can you please help me with this? 
 agent: Sure, may I know your name please? 
 customer: My name is Anthony Phillips. 
 agent: Please wait a moment. 
 customer: Sure. 
 agent: Unfortunately there is no reservation found with your given name. 
 customer: Not a problem, thank you for checking. 
 agent: Thank you for choosing us.
Solution: no_reservation
Reason: Here the customer has not asked for any booking, he just wanted to update his already booked flight, so the status would be no_reservation

Now, solve this instance: customer: Hello, I am Susan Thompson. 
 agent: Hello, how may I assist you? 
 customer: I want to visit 16th street mall at Denver, please book a connecting flight. 
 agent: Sure, may I know your price limit to book a ticket? 
 customer: I need the ticket within price 500. 
 agent: Ok, what dates you would like to travel? 
 customer: I want to fly on 12/28 and return on 12/30. 
 agent: May I know your airport codes? 
 customer: My origin airport code is TX- DFW and Dest airport code is CO- DEN. 
 agent: Ok, there is a flight 1004 in Southwest airline matching your requirements with price 300. Shall I proceed with this airline? 
 customer: Please proceed with booking. 
 agent: Ok, your ticket has been booked. 
 customer: Thank you for the reservation. 
 agent: Thanks for reaching us. Have a safe journey!.
Student:
book