Caine: But Master Po, I have learned everything you have taught me. When will it be time for me to leave?

Po: You have done well, Grasshopper, and we are pleased. When you can show us a 6.5 inch 627 on top with a 4 inch on the bottom and a 686 in the middle, it will be time for you to leave.

(Actual "Kung Fu" script quote before redaction.)