The guardians of the galaxy!
or
Two. One to take out the bulb and drop it, and the other to try and sell it before it crashes (knowing that it's already burned out).
or
A crossing guard.
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None. There never was any light bulb.
Notes: Probably the only really good light bulb joke of 1984.
or
Bike helmets don't fit hippos
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Because it goes good with chips.
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Pointless
or