- `hashes` - string of hashes representing header level (e.g., "###")
    - `permalink` - permalink string (e.g., "{#permalink}")
    """

    headers: list[HeaderPermalinkInfo] = []
    in_code_block3 = False
    in_code_block4 = False

    for line_no, line in enumerate(lines, start=1):
        if not (in_code_block3 or in_code_block4):
            if line.startswith("```"):

markdown_extensions:
  material.extensions.preview:
    targets:
      include:
      - '*'
  abbr: null
  attr_list: null
  footnotes: null
  md_in_html: null
  tables: null
  toc:
    permalink: true
  pymdownx.betterem: null
  pymdownx.caret: null
  pymdownx.highlight:
    line_spans: __span
    linenums_style: pymdownx-inline
  pymdownx.inlinehilite: null
  pymdownx.keys: null

            if match:
                hashes, title, _permalink = match.groups()
                if (not _permalink) or update_existing:
                    slug = slugify(
                        visible_text_extractor.extract_visible_text(
                            strip_markdown_links(title)
                        )
                    )
                    if slug in permalinks: