Definition: 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
Input: customer: Hello. 
 agent: Hello, how can I help you today? 
 customer: Can you please help me to book a flight from HOU to SEA? 
 agent: Sure, can you please mention your depart and arrival dates of your journey? 
 customer: My travel dates are Apr 06 to 08. 
 agent: Do you have any connection limit? 
 customer: I prefer connecting flight. 
 agent: Are there any other specifications? 
 customer: No. 
 agent: Can I know your good name? 
 customer: I am Alexander Turner. 
 agent: Sorry, no flights are available in this route as per your requested dates. 
 customer: No problem, thank you for the information. 
 agent: Thank you for reaching us.
Output:
no_flight