def check_clean_bg(self):
        """Store a clean bg if scrollable.

        This method also perform this same check recursively
        in all children.
        """
        ### if the menu is scrollable, copy the body
        ### image into a clean_bg attribute, which will
        ### be used to clean the body image attribute

        if self.is_scrollable():
            self.clean_bg = self.body.image.copy()

        ### check children, too

        for child in self.children:

            ## store method if it exists
            try:
                method = child.check_clean_bg

            ## if it doesn't, just pass
            except AttributeError:
                pass

            ## otherwise, execute it
            else:
                method()
Store a clean bg if scrollable.

        This method also perform this same check recursively
        in all children.
        
nodezator/menu/submenu/scroll.py