code: def parse_html(html):
      
      body = html.strip().replace('\x00', '').encode('utf8') or b'<html/>'
      parser = lxml.html.HTMLParser(recover=True, encoding='utf8')
      root = lxml.etree.fromstring(body, parser=parser)
      if root is None:
          root = lxml.etree.fromstring(b'<html/>', parser=parser)
      return root
docs: Create an lxml.html.HtmlElement from a string with html.
      XXX: mostly copy-pasted from parsel.selector.create_root_node