code: def assignee(self, assignee_id, action='ADD'):
          
          if not self.can_update():
              self._tcex.handle_error(910, [self.type])
  
          return self.tc_requests.assignee(
              self.api_type, self.api_sub_type, self.unique_id, assignee_id, action=action
          )
docs: Adds a assignee to the task
  
          Args:
              assignee_id: The id of the assignee to be added
              action: