Teacher: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
Teacher: Now, understand the problem? Solve this instance: customer: Hello. 
 agent: Hello. How may I help you? 
 customer: I want to take my students to Denver Museum of Nature and Science in Denver - DEN, can you please find a flight from ATL? 
 agent: Could you please share me your travel dates? 
 customer: I will start on Oct 14th and return on Oct 16th. 
 agent: Is there any other requirements? 
 customer: I want to depart in the evening time. 
 agent: Do you have any other preference? 
 customer: I am fine with maximum one connection. 
 agent: Do you prefer any class? 
 customer: I am comfortable with any class. 
 agent: Please wait for a while. 
 customer: Sure. 
 agent: Sorry for inconvenience, no flights are found with your criteria. May I know your name please? 
 customer: My name is Linda Rodriguez. Not to worry, thank you for the information. 
 agent: Thank you very much for contacting our agency.
Student:
no_flight