Bugfix

The model receives the prompt (and optional system message). The run uses scorer contains_all with the JSON configuration below. Pass/fail and partial credit are determined entirely by that scorer against the model output; no human grading.

Fix the bug and return corrected Python code only.\n\ndef latest(items):\n    if len(items) == 0:\n        return items[-1]\n    return None\n

{
  "expected_contains": [
    "if len(items) == 0",
    "return None",
    "items[-1]"
  ]
}