code: func (c *Cleaner) cleanParaSpans(doc *goquery.Document) *goquery.Document {
  	spans := doc.Find("span")
  	spans.Each(func(i int, s *goquery.Selection) {
  		parent := s.Parent()
  		if parent != nil && parent.Length() > 0 && parent.Get(0).DataAtom == atom.P {
  			replaceTagWithContents(s, whitelistedTextAtomTypes)
  		}
  	})
  	return doc
  }
docs: // Replace <p><span>...</span></p>   with  <p>...</p>