Given the task definition, example input & output, solve the new input case.
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: 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.
Output: no_reservation
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

New input case for you: customer: Hi, Margaret Evans is my name. 
 agent: Hello, how may I help you? 
 customer: I am willing to book a flight on Oct 25th to reach Philadelphia, so please help me in booking a flight with a halt. 
 agent: Sure, may I know your source and destination airport codes? 
 customer: Sure, my airport codes are HOU - PHL. 
 agent: Ok, when you will return from PHL? 
 customer: I have planned to return on 27th of Oct. 
 agent: Please wait a moment to check flight availability. 
 customer: Sure. 
 agent: We found a flight from Spirit airline with 1 connection and the fare is 100 with an economy class.Shall I proceed? 
 customer: Ok, please confirm my booking. 
 agent: Your ticket is booked with 1008 flight number. 
 customer: Thank you. 
 agent: Thank you for reaching us.
Output:
book