def showPrevTab(self):
        """ showPrevTab() -> None
        Bring the previous tab up

        """
        if self.operatingWidget.currentIndex()>0:
            index = 1-self.operatingWidget.currentIndex()
            self.operatingWidget.setCurrentIndex(index)
dataset/ETHPy150Open VisTrails/VisTrails/vistrails/packages/spreadsheet/spreadsheet_tabcontroller.py/StandardWidgetTabController.showPrevTab/swapped operands of `-`