"Self-Defence Against Fresh Fruit" is a Monty Python sketch that appeared in the episode "Owl Stretching Time". It is about an RSM-type instructor who is teaching a class about self-defense, but all he teaches is how to defend oneself against an assailant "armed" with a piece of fresh fruit.
The first half or so of the sketch was remade for the Pythons' first feature film, And Now for Something Completely Different.
The teacher (John Cleese) is about to start off his class, but he notices that everyone, save for four students, is absent. He starts off the class by carrying on from where they got to last week when he was showing them how to defend themselves against anyone who attacks with a piece of fresh fruit. The class complains that for the last nine weeks, all he's been teaching them is fruit. One student (Eric Idle) keeps on insisting that they should be taught how to defend themselves against anyone who attacks with a pointed stick. The teacher berates the student for thinking that pointed sticks are more dangerous than fresh fruit, saying, in a drill-sergeant style tone of voice, "Ooh, ooh, ooh; we want to learn how to defend ourselves against pointed sticks, do we? Getting all high and mighty, eh? Fresh fruit not good enough for you, eh? Well, let me tell you something, my lad! When you're walking home tonight and some great homicidal maniac comes after YOU with a bunch of loganberries, don't come cryin' to me!"
He starts off the class with passionfruit, but the whole class complains that they've already done passionfruit, in addition to oranges, apples, grapefruit (whole and segmented), pomegranates, greengages, grapes, lemons, plums, mangoes in syrup, and cherries (red and black). The teacher then hits upon the fact he has yet to teach them about bananas. He tells them, to defend themselves against a man armed with a banana, first, he has to be forced to drop the banana, then the banana has to be eaten, thus disarming him and rendering him helpless. When another student (Michael Palin) asks about a man armed with a bunch of bananas, the teacher tells him to shut up. He demonstrates by asking a student called Mr. Harrison (Graham Chapman, whom the teacher calls Mr. Apricot), to attack him with a banana, but just as Harrison is about to attack him, the teacher shoots him dead and eats the banana. (The movie version ends here.)