code: def _serve_dir(self, abspath, params):
      
      relpath = os.path.relpath(abspath, self._root)
      breadcrumbs = self._create_breadcrumbs(relpath)
      entries = [{'link_path': os.path.join(relpath, e), 'name': e} for e in os.listdir(abspath)]
      args = self._default_template_args('dir.html')
      args.update({'root_parent': os.path.dirname(self._root),
                   'breadcrumbs': breadcrumbs,
                   'entries': entries,
                   'params': params})
      content = self._renderer.render_name('base.html', args).encode("utf-8")
      self._send_content(content, 'text/html')
docs: Show a directory listing.