code: def get_identifier(self, origin=None):
          
  
          token = self.get().unescape()
          if not token.is_identifier():
              raise dns.exception.SyntaxError('expecting an identifier')
          return token.value
docs: Read the next token and raise an exception if it is not an identifier.
  
          @raises dns.exception.SyntaxError:
          @rtype: string