class_docstr: Stateful operator
code: def __call__(self, num: int) -> NamedTuple("Outputs", [("sum", int)]):
      Outputs = NamedTuple("Outputs", [("sum", int)])
      return Outputs(self._factor + num)
  
imports: from typing import NamedTuple
  from towhee.operator import PyOperator, SharedType
label_desc: Use image node_id 2 for calling the AddOperator obj's underlying member method code with example usage: obj.__call__(num) and returns: Outputs