code: def contents_list_pairs(self):
          '''Iterator over pairs of normal and hidden contents'''
          return (tuple(getattr(self.generator, name) for name in names)
                  for names in self.info.get('contents_lists', [])f contents_list_pairs(self):
          '''Iterator over pairs of normal and hidden contents'''
          return (tuple(getattr(self.generator, name) for name in names)
                  for names in self.info.get('contents_lists', []))
docs: Iterator over pairs of normal and hidden contents