code: def test_docs(self):
      raise NotImplementedError()
  
imports: import numpy
  import sacrebleu
  import datasets
  from rouge_score import rouge_scorer, scoring
  from lm_eval.base import rf, Task
  from lm_eval.metrics import mean
  from lm_eval.utils import bleu, rouge
label_desc: Use image node_id 8 for calling the TruthfulQAGeneration obj's underlying member method code with example usage: obj.test_docs() without return types