You will be given a definition of a task first, then some input of the task.
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, myself Sharon Hernandez. 
 agent: Hello, how may I help you? 
 customer: Can you please help me in booking a flight ticket from SFO to DTW locations? 
 agent: Sure, please share your travel dates. 
 customer: My travelling dates are from 08/04 and 08/06. 
 agent: Sorry, no flights available at this moment. 
 customer: It' sok. thank you for the information. 
 agent: Thank you for reaching us.
Output:
no_flight