Two — one to change the bulb, and one to write a song about how good the old light bulb was.
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Just one, provided there is a programmer around to explain how to do it.
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What's the use, they'd still have bear feet
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One; she designs the bulb to crawl up the wall, unscrew the old one, and screw itself in.
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That's proprietary information. The answer is available from AT&T on payment of license fee (binary only).
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Can I have your hand, hand, hand, hand, hand, hand, hand, hand in marriage?
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Because he wanted to be on time.
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