code: def _parse_users(self, match):
          '''Parse usernames.'''
  
          # Don't parse lists here
          if match.group(2) is not None:
              return match.group(0)
  
          mat = match.group(0)
          if self._include_spans:
              self._users.append((mat[1:], match.span(0)))
          else:
              self._users.append(mat[1:])
  
          if self._html:
              return self.format_username(mat[0:1], mat[1:]f _parse_users(self, match):
          '''Parse usernames.'''
  
          # Don't parse lists here
          if match.group(2) is not None:
              return match.group(0)
  
          mat = match.group(0)
          if self._include_spans:
              self._users.append((mat[1:], match.span(0)))
          else:
              self._users.append(mat[1:])
  
          if self._html:
              return self.format_username(mat[0:1], mat[1:])
docs: Parse usernames.