Fix Split Join

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.

def csv_to_list(s):
    return s.join(",")

{
  "expected_contains": [
    "s.split(\",\")"
  ]
}