Multi-turn user requests:
user: Imagine planning a trip and you're curious about the flight costs between various airports. Opt to fly from the first airport to the second one in the system's list. Could you provide the expected fare for an economy class ticket on the date 2024-11-15?
user: Good news! You've discovered a fare that won't break the bank. Next, let's arrange a flight from San Francisco International (SFO) to Los Angeles International (LAX). Utilize a distinctive access token 'abc123xyz', the credit card with id 'card_3456', and the traveler details of our intrepid voyager, Elizabeth Montgomery.
user: Finally, Elizabeth seeks some tranquility during her adventure. Please acquire travel insurance for this booked flight, selecting a plan that offers up to $500 coverage. You are welcome to use the same credit card and access token for this purchase.

Tools involved: TravelAPI
Expected function-call sequence: TravelAPI.list_all_airports
TravelAPI.get_flight_cost
TravelAPI.book_flight
TravelAPI.purchase_insurance