user_query: Add an item to the to-do list.
response_text: What do you want to add?
user_query: Add it to my shopping list instead.
response_text: You have two items on that list. Which one do you want to edit?
User: I want to add yoga mat to my shopping list.
Parse: Add_item_to_list ( items « yoga mat » list_label « shopping » list_singular_or_plural « list » )