Given the task definition and input, reply with output. 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 can I assist you? 
 customer: I am Anna Collins. I am planning to attend singing computation in  LAS, can you help in finding a flight from JFk? 
 agent: Can you please share on what dates you are willing to travel? 
 customer: I will be traveling on 02/15 and I might be return on 02/17. 
 agent: Please hold on a minute, I will get back with your details. 
 customer: Sure, take your own time. 
 agent: There is a flight available with 100 price, flight number is 1011.Shall I proceed the booking? 
 customer: Yes please proceed for booking with that flight. 
 agent: Number of connections are 2. 
 customer: Oh I want to travel in single connection flight. 
 agent: I am sorry, there is no flight with that connection. 
 customer: That's ok, thank you for your help. 
 agent: Thank you for reaching us.
no_flight