You can't. You have to use the power button located on your macintosh.
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On the Feast of St.Stephen, I was driving my hearse to the wholesale liverwhurst outlet when suddenly a hermaphrodite in a piano truck backed out of a crackhouse driveway, and, as my shoes caught fire, I pirouetted across Boris Karloff Boulevard, slapping the truckdriver six times in the loin with a Chattanooga road map, even though he was humming the "The Pussycat Song."