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: Hello,. 
 agent: Hello, how can I help you today? 
 customer: I have planned to travel from Houston, TX- IAH to Atlanta, GA- ATL. 
 agent: Sure, please provide me your journey dates? 
 customer: Sure, my travelling dates are from depart day on 11th Nov and return on 13th Nov. 
 agent: OK, please wait I will revert you in a while. 
 customer: OK, sure. 
 agent: Thank you for your patience. Sorry, there were no flights available on the specified  dates you mentioned. May I know your good name? 
 customer: OK, no issues. Thank you the information. I am Mary Jackson. 
 agent: OK, thank you for contacting us, have a good day.
Example Output: no_flight

Example Input: customer: Hi. 
 agent: Hello, how can I help you? 
 customer: I am Elizabeth Gonzalez. I am looking for a direct flight from IAH to DTW, please book my flight ticket. 
 agent: May I know your desired travel dates please? 
 customer: Sure, I want to depart on Dec 4th and I have to return back in the afternoon on Dec 6th. 
 agent: Please wait a while. 
 customer: Sure. 
 agent: There is a flight with connection limit 1 and fare 200, shall I proceed for booking? 
 customer: No, I prefer for a direct flight. 
 agent: Sorry to say, there is no flight available on your desired travel dates. 
 customer: Sad to hear that, thank you for checking. 
 agent: Thank you for opting us.
Example Output: no_flight

Example Input: customer: Hi. 
 agent: Hello. How can I help you? 
 customer: Ashley Garcia here. My trip was postponed and I want to change my reservation can you help me? 
 agent: Please give me a minute. Sorry, there is no reservation found under your name. 
 customer: No problem. 
 agent: Thank you for reaching us. 
 customer: Thank you for checking. 
 agent: You are welcome.
Example Output:
no_reservation