docs: def get_content_html(request):
      """Retrieve content as HTML using the ident-hash (uuid@version)."""
      result = _get_content_json()
  
      media_type = result['mediaType']
      if media_type == COLLECTION_MIMETYPE:
          content = tree_to_html(result['tree'])
      else:
          content = result['content']
  
      resp = request.response
      resp.body = content
      resp.status = "200 OK"
      resp.content_type = 'application/xhtml+xml'
      return result, resp