docs: def adapt_single_html(html):
      """Adapts a single html document generated by
      ``.formatters.SingleHTMLFormatter`` to a ``models.Binder``
      """
      html_root = etree.fromstring(html)
  
      metadata = parse_metadata(html_root.xpath('//*[@data-type="metadata"]')[0])
      id_ = metadata['cnx-archive-uri'] or 'book'
  
      binder = Binder(id_, metadata=metadata)
      nav_tree = parse_navigation_html_to_tree(html_root, id_)
  
      body = html_root.xpath('//xhtml:body', namespaces=HTML_DOCUMENT_NAMESPACES)
      _adapt_single_html_tree(binder, body[0], nav_tree, top_metadata=metadata)
  
      return binder