Two — one to change the bulb, and one to write a song about how good the old light bulb was.
or
Time is fun when you're having flies
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Only one, but she/he'll have to go out and buy the light bulb adaptor card first, which is extra.
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Norse code.
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Two. One to change the bulb, and one to write a song about how good the old light bulb was.
or