def setBackground(self,bg):
        """
        Sets the background of the Container.
        
        Similar to :py:meth:`peng3d.gui.SubMenu.setBackground()`\ , but only effects the region covered by the Container.
        """
        self.bg = bg
        if isinstance(bg,list) or isinstance(bg,tuple):
            if len(bg)==3 and isinstance(bg,list):
                bg.append(255)
            self.bg_vlist.colors = bg*4
        elif bg in ["flat","gradient","oldshadow","material"]:
            self.bg = ContainerButtonBackground(self,borderstyle=bg,batch=self.batch2d)
            self.redraw()
Sets the background of the Container.
        
        Similar to :py:meth:`peng3d.gui.SubMenu.setBackground()`\ , but only effects the region covered by the Container.