user_query: add go on walk on my to-do list 
response_text: Got it, I added go on walk.
user_query: To-do list 
response_text: You have one thing on that list.
User: I want to start a 1 hour session of racquetball, no make that pickleball.
Parse: Start_exercise ( activity « pickleball » duration « 1 hour » )