Detailed Instructions: 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
Q: customer: Hello. 
 agent: Hello, how may I aid you for today? 
 customer: Dennis Parker here. I am a social activist, I have to host a campaign against gun culture at Detroit. So please book my ticket from Denver. 
 agent: I am glad to help you with that. Can you please let me know your planned dates of your journey? 
 customer: My itinerary dates are 06/30 and 07/02. 
 agent: Certainly, please provide your nearest airport codes. 
 customer: My genesis and terminus airport codes are DEN and DTW. 
 agent: Please wait for a while, I will get a suitable flight for your journey. 
 customer: Sure. 
 agent: Sorry to say this Parker, there are no flight which can travel to your region on your planned dates of your journey. 
 customer: No problem, thank you for checking. 
 agent: You are welcome, thank you for reaching out here. Hope you have a nice day.
A:
no_flight