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

Ex Input:
customer: Hello, I am Sandra Taylor. 
 agent: Hello, how may I aid you? 
 customer: I want to change an existing reservation, can you please help me in that? 
 agent: Sure, I am here to help you. Please wait for a while. 
 customer: Sure. 
 agent: Thanks for your time, there is no active reservation found in your name. 
 customer: That's ok, not a problem. Thanks for your information. 
 agent: Thank you for choosing us.

Ex Output:
no_reservation


Ex Input:
customer: Hello. 
 agent: Hello. 
 customer: I am Elizabeth Walker. 
 agent: How may I assist you today? 
 customer: Will you please assist me in booking a flight ticket from ATL to CLT? 
 agent: Sure, may I know your travelling dates, please? 
 customer: I am planning to depart on June 07 and return on June 09. 
 agent: Do you need any specification? 
 customer: I need a halt in between my journey. 
 agent: Sorry, there are no flight tickets available on your journey dates. 
 customer: Ok, no problem. 
 agent: Thank you for reaching our service. 
 customer: Thank you for the information.

Ex Output:
no_flight


Ex Input:
customer: Hello. 
 agent: Hello. 
 customer: Jonathan Adams here. 
 agent: Adams, how may I aid you? 
 customer: I need to cancel my recent reservation due to snowfall, can you please  guide me? 
 agent: Sure, please give me a moment to check your ticket status. 
 customer: Take your time. 
 agent: Sorry, no reservation is available by your name. 
 customer: That's not an issue, thank you for helping me. 
 agent: Thank you for contacting us.

Ex Output:
no_reservation