Before the code I shared, there were some lines like this

step_base_task = Task.get_task(project_name=cfg[name]['base_project'],
                               task_name=cfg[name]['base_name'])
export_data = step_base_task.export_task()

... modify export_data in-place ...

task = Task.import_task(export_data)
pipe.add_step(base_task_id=task.id, clone_base_task=False, ...)