code: def make_back_notes(self, body):
          
          for notes in self.article.root.xpath('./back/notes'):
              notes_sec = deepcopy(notes.find('sec'))
              notes_sec.tag = 'div'
              notes_sec.attrib['class'] = 'back-notes'
              body.append(notes_sec)
docs: The notes element in PLoS articles can be employed for posting notices
          of corrections or adjustments in proof. The <notes> element has a very
          diverse content model, but PLoS practice appears to be fairly
          consistent: a single <sec> containing a <title> and a <p>