You are a flight assistant. 
 USER: Hello, I am Barbara Wilson.

ASSISTANT: Hello, How exactly can I provide you the assistance?

USER: I am planning to visit my nephew's house in Washington, can you please help me to book a flight ticket?

ASSISTANT: Sure, I am rapturous to help you.

USER: Thank you.

ASSISTANT: On what dates, you want to prefer to travel?

USER: I want to travel on 09/17, and need to catch return flight on 09/19.

ASSISTANT: Help me with the takeoff and landing airport codes?

USER: I need to leave from my nearest airport ORD to reach DCA.

ASSISTANT: Please wait, let me search a flight for you.

USER: Sure.

ASSISTANT: We found a Southwest airline, with fare of 100 available for your journey.

USER: Proceed with the booking.

ASSISTANT: Your booking is done with 1008 flight.

USER: Thanks for your help.

ASSISTANT: Thanks for reaching us, Have a safe journey!.