code: def check_input(self, token):
          
          if isinstance(token.payload, Evaluation):
              return None
          if isinstance(token.payload, ClusterEvaluation):
              return None
          raise Exception(
              self.full_name + ": Input token is not a supported Evaluation object - "
              + classes.get_classname(token.payload))
docs: Performs checks on the input token. Raises an exception if unsupported.
  
          :param token: the token to check
          :type token: Token