user_query: create a list under Library name
response_text: Alright, I made a list called "Under Library".
user_query: create a list name library 
response_text: Alright, I made a list called "Library".
user_query: add return books 
response_text: OK. Return books on your list called "Library". Anything else?
user_query: add renew my library card
response_text: Alright. Renew my library card. Anything else?
User: Get some gas gas from Chevron.
Parse: Get_product ( product « gas » product_source « Chevron » )