Sample code of model graders for reinforcement fine-tuning is not working

API Bugs
1

I copied the full runnable code sample from OpenAI’s official documentation:
https://platform.openai.com/docs/guides/graders#model-graders

The code is about implementing a model-based grader for reinforcement fine-tuning.

However, after running the Python script, the output is:

validate response: {
  "error": {
    "message": "Unknown grader type: label_model",
    "type": "invalid_request_error",
    "param": null,
    "code": "grader_error"
  }
}
run response: {
  "error": {
    "message": "Unknown grader type: label_model",
    "type": "invalid_request_error",
    "param": null,
    "code": "grader_error"
  }
}

Which, I guess, is due to the obsolete API?