user_query: add butter to list called shopping 
response_text: Alright, I added butter.
user_query: remove flour off list called shopping 
response_text: Alright, I deleted flour.
user_query: Add flour to list called shopping 
response_text: Sure, I added flour.
User: Get my Georgia Power statement for this billing cycle.
Parse: Get_bill ( account_provider « Georgia Power » billing_cycle « this billing cycle » )