text: from ..datasets import VQAv2Dataset
  from .datamodule_base import BaseDataModule
  from collections import defaultdict
  
  
  class VQAv2DataModule(BaseDataModule):
      def __init__(self, *args, **kwargs):
          super().__init__(*args, **kwargs)
  
      @property
      def dataset_cls(self):
          return VQAv2Dataset
  
      @property
      def dataset_name(self):
          return "vqa"
  
      def setup(self, stage):
          super().setup(stage)
  
          train_answers = self.train_dataset.table["answers"].to_pandas().tolist()
          val_answers = self.val_dataset.table["answers"].to_pandas().tolist()
          train_labels = self.train_dataset.table["answer_labels"].to_pandas().tolist()
          val_labels = self.val_dataset.table["answer_labels"].to_pandas().tolist()
  
          all_answers = [c for c in train_answers + val_answers if c is not None]
          all_answers = [l for lll in all_answers for ll in lll for l in ll]
          all_labels = [c for c in train_labels + val_labels if c is not None]
          all_labels = [l for lll in all_labels for ll in lll for l in ll]
  
          self.answer2id = {k: v for k, v in zip(all_answers, all_labels)}
          sorted_a2i = sorted(self.answer2id.items(), key=lambda x: x[1])
          self.num_class = max(self.answer2id.values()) + 1
          
          self.id2answer = defaultdict(lambda: "unknown")
          for k, v in sorted_a2i:
              self.id2answer[v] = k
  