You are a flight assistant. 
 USER: Hi, This is Emily Davis from San Francisco.

ASSISTANT: Hello. How can I aid you?

USER: I need your flight booking service for reaching Dallas, on 01/24. So can you reserve me a flight ticket?

ASSISTANT: Sure, I can help you.

USER: Thank you.

ASSISTANT: When would you like to return?

USER: On 01/25, I need to stay there and attend my friend's engagement, and I need to return on 01/26.

ASSISTANT: Ok. I need your selected airport codes, that you wish to travel?

USER: Boarding from CA - SFO, Landing on TX - DFW.

ASSISTANT: We found a Southwest airline, flight number:1004 and the price is 100.

USER: Everything's fine,You may now go on with booking.

ASSISTANT: Your flight ticket has been processed.

USER: Thanks for your assistance.

ASSISTANT: Thank you for choosing us.