user_query: Tell me what's on my music list.
response_text: You have two things on that list. They're Metallica and scorpion, Scorpions.
user_query: I also need to delete scorpion from music list
response_text: I couldn't find scorpion on your list called "Music."
user_query: Cancel that delete metallica and scorpion from music list
response_text: Alright, I deleted Metallica.
user_query: Add Metallica and scorpion to music list
response_text: OK, I added Metallica and scorpion.
User: Please uh get me cat food.
Parse: Get_product ( product « cat food » )