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

customer: Hello. 
 agent: Hello, how may I help you? 
 customer: Can you please reserve me a flight ticket from DFW to SFO? 
 agent: Sure, I am here to help you. Can you please share your travel dates? 
 customer: My planned dates of journey are Aug 11 and Aug 13. 
 agent: May I know your name? 
 customer: My name is Gary Evans. 
 agent: May I know your connection limit? 
 customer: I prefer connecting flight. 
 agent: Is there any preferences? 
 customer: I prefer normal cost airlines for this trip. 
 agent: Sorry, there are no flights found on your travel dates. 
 customer: Ok, not an issue. Thank you for providing information. 
 agent: Thank you for choosing us.
no_flight