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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def AltTab(self, n=1, delay=0):
 """Press down Alt, then press n times Tab, then release Alt. """

        self._delay(delay)
        self.add(Command("KeyDown", 'KeyDown "%s", %s' % (BoardKey.Alt, 1)))
        for i in range(n):
            self.add(Command("KeyPress", 'KeyPress "%s", %s' % (BoardKey.Tab, 1)))
        self.add(Command("KeyUp", 'KeyUp "%s", %s' % (BoardKey.Alt, 1)))