code: def download(self):
      raise NotImplementedError(
          "This dataset is now under test and cannot be downloaded."
          "Please prepare the raw data yourself."
      )
  
imports: import nltk
  from ..data.dataset import DoubleText2TextDataset
label_desc: Use image node_id 3 for calling the SQuADDataset obj's underlying member method code with example usage: obj.download() without return types