def collapse_siblings(self):
        """Collapse all sibling items.

        Sibling items are either other commands and/or
        menu.submenu.main.Menu instances.
        """
        for child in self.parent.children:

            if hasattr(child, "is_expanded"):
                child.is_expanded = False
Collapse all sibling items.

        Sibling items are either other commands and/or
        menu.submenu.main.Menu instances.
        
nodezator/menu/command.py