Whenever your friends John and Judy visit you together, y'all have a party 🥳. Given a DataFrame with 10 rows representing the next 10 days of your schedule and whether John and Judy are scheduled to make an appearance, insert a new column called days_til_party that indicates how many days until the next party.
days_til_party should be 0 on days when a party occurs, 1 on days when a party doesn't occur but will occur the next day, etc.