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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 mouseDown(self, button):
 """ Send a mouse button down at the last set position button: int: [1-n] """

        log.debug('mouseDown %s', button)
        self.buttons |= 1 << (button - 1)
        self.pointerEvent(self.x, self.y, buttonmask=self.buttons)

        return self