Hello, I am facing the same issue, my job is in .yml form, which I copied from UI after creating the for_each_task loop and selecting "Switch to code version (yaml)". Even after copying it as it is, getting the same error, here is the reference yaml:
```

- task_key: my_custom_task
  depends_on:
    - task_key: my_previous_task
  for_each_task:
    inputs: "{{tasks.my_previous_task.values.parameter1}}"
    task:
      task_key: my_custom_task_iteration
      python_wheel_task:
        package_name: custom_package
        entry_point: program_main
        parameters:
          - --config-path
          - .....
          - "{{input}}"
      job_cluster_key: custom_cluster
      libraries:
        - whl: ....
```