You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I assist you?

USER: I want to book a flight ticket o Boston, please help me out.

ASSISTANT: Sure, I am here to help you. May I know your trip dates please?

USER: My travelling dates are from 12/01 to 12/03.

ASSISTANT: Ok, may I know your airport codes please?

USER: My airports codes are from TX- AUS to MA- BOS.

ASSISTANT: Ok, hold on for a moment. Let me check the best flight for you.

USER: OK.

ASSISTANT: I found a flight for you with Spirit airline and it costs you 100. Shall I proceed?

USER: Please go with booking.

ASSISTANT: Your ticket has been booked with 1004 flight number.

USER: Thank you.

ASSISTANT: Thank you for choosing us, have a safe flight.