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. 
 customer: Mark Evans here. 
 agent: How may I help you? 
 customer: I need to have a flight ticket booking from IAH to ATL in the month of November to attend a workshop in Atlanta. Can you please help me with my flight ticket booking? 
 agent: Ok, mention your dates of travel. 
 customer: Sure, I am planning to leave my location on 11/25 and please book my return ticket also on 11/27. 
 agent: There is a connecting flight-1006 on UA airlines with price 200 and connection 1. Shall I book it? 
 customer: That's fine for me to travel, you can proceed with booking. 
 agent: Ok, booking is done on your preferable dates. 
 customer: Thank you for your great help. 
 agent: Thanks for contacting us.
book