Restore all items expanded state

def restore_expanded_state(self):
        """Restore all items expanded state"""
        if self.__expanded_state is None:
            return
        for item in self.get_items()+self.get_top_level_items():
            user_text = get_item_user_text(item)
            is_expanded = self.__expanded_state.get(hash(user_text))
            if is_expanded is not None:
                item.setExpanded(is_expanded)