user_query: Would you add Hawaii to the Trips to Plan list?
response_text: I couldn't find a list called "Trips To Plan." Do you want me to make one?
user_query: Yes
response_text: Alright, I made a list called "Trips To Plan" and added Hawaii.
User: Sorry, I meant to add Las Vegas to the Trips to Plan list
Parse: Add_item_to_list ( items « Las Vegas » list_label « Trips to Plan » list_singular_or_plural « list » )