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? Solve this instance: customer: Hello, Margaret Green here. 
 agent: Hello, how can I assist you today? 
 customer: I got a job at Detroit and for documentation purpose I need to go there on 02/17, so please book me a flight ticket on 02/16 along with a return ticket on 02/18. 
 agent: Sure, can you please share your journey points? 
 customer: My source point is LAX and destination point is DTW. 
 agent: Do you have any requirements? 
 customer: I will prefer a connecting flight. My budget is 1000. 
 agent: Please wait for a while, I will check and get back to you. 
 customer: Ok. 
 agent: Thanks for your patience, We found a direct flight with your given details. Shall I proceed? 
 customer: Please don't proceed then. Thank you for your information. 
 agent: Ok. Thanks for choosing us.
Student:
no_flight