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

Example input: 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.
Example output: no_reservation
Example explanation: 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
Q: customer: Hello, I am Susan Smith. 
 agent: Hello Susan Smith. What kind of service you are expecting from us? 
 customer: I want to book a ticket from DCA to MSP for visiting Mill city museum. Can you help me in that? 
 agent: Sure, we are here to help you. Kindly mention your preferable dates on which you want to travel? 
 customer: My travelling dates are 10/21 to 10/23. 
 agent: Do you have any other specifications to be met? 
 customer: Yes, My price limit is 5000 with single connection. 
 agent: We are glad to inform you that we found an UA airline which is as per your requirement. Shall I proceed to book? 
 customer: Ok, You please proceed with it. 
 agent: Your booking has been reserved with flight number 1024. 
 customer: Thank you for your service. 
 agent: Thanks for contacting us, have a pleasant journey.
A:
book