None. They just let Marketing explain that "Dead Bulb" is a feature.
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The man says: "You go up there and tell him off. Go on, I'll hold your monkey for you."
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One's a spineless, poisonous blob. The other is a form of sea life.
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Does it have to be a light bulb? I've got this neat candle holder...
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Bozo The Clown has real hair on his head.
or