class_docstr: An item in MkDocs structure - see concrete subclasses Section, Page or Link.
code: def is_top_level(self) -> bool:
      return self.parent is None
  
imports: from __future__ import annotations
  import abc
  from typing import TYPE_CHECKING, Iterable
label_desc: Use image node_id 2 for calling the StructureItem obj's underlying member method code with example usage: obj.is_top_level() and returns: unknown