Two. One to take out the bulb and drop it, and the other to try and sell it before it crashes.
or
You're the only bright spot in my life.
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Two. One to screw it in, and one to stab the other in the back and take all the credit.
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Only one, but the bulb has got to really WANT to change.
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A garbage truck.
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What's the use, they'd still have bear feet
or