The absolute best way for a Canadian to ripen a papaya:

1) Wrap papaya tightly in plastic bag.
2) Insert plastic-wrapped papaya into suitcase
3) Fill balance of suitcase with warm-weather clothing
4) Call taxicab
5) Have taxicab take you to airport
6) Purchase round-trip ticket to Cuba
7) Upon arrival in Cuba, find a fruit vendor selling papayas
8) Remove your papaya from suitcase
9) Throw your papaya in nearest trash receptacle
10) Purchase ripe papaya from fruit vendor