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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 setFullscreen(self, fullscreen):

 """toggle between fullscreen and normal window"""

        if not fullscreen:
            self.ckBox_fullscreen.setChecked(False)
            self.parent().showNormal()
        else:
            self.ckBox_fullscreen.setChecked(True)
            self.parent().showFullScreen()