user_query: add water to my grocery list
response_text: Got it, I added water.
user_query: don't add water, but put juice on the grocery list
response_text: I couldn't find that item on your list called "grocery."
user_query: add water
response_text: Alright. Which list do you want to add to?
user_query: scratch that add juice instead
response_text: OK. Which list do you want to add to?
User: Check my Verizon, I mean AT&T bill.
Parse: Get_bill ( account_provider « AT&T » )