def deadline(self):
        if self.estimation_value > 0:
            duration = datetime.timedelta(
                    seconds=(self.estimation_value*self.estimation_unit)
                    )
            return (self._today()+duration)
        else:
            return None
Will return the expected deadline (or None) for this state calculated
dataset/ETHPy150Open ntoll/workflow/workflow/models.py/State.deadline