So “wait” is a better metaphore for me

So I would do something like (I might have a few typos but that's the gist):

def post_execute_callback_example(a_pipeline, a_node):
    # type (PipelineController, PipelineController.Node) -> None
    print('Completed Task id={}'.format(a_node.executed))
    # wait until model is tagged, then pass it as argument
    while True:
        found = Moodel.query_models(...) # model filter here, inlucing tag and project
        if found:
            break
        print('waiting for model taggging')
        sleep(60)
    # find the actual next step node and pipe the model model ID
    next_step_node= a_pipeline.get_pipeline_dag()['next_step_name_here']
    next_step_node.parameters['Args/model_id'] = found[0].id
    return

pipe.add_step(name='stage_process', parents=['stage_data', ],
              base_task_project='examples', base_task_name='pipeline step 2 process dataset',
              parameter_override={'General/dataset_url': '${stage_data.artifacts.dataset.url}',
                                  'General/test_size': 0.25},
              post_execute_callback=post_execute_callback_example
              )

WDYT?