class_docstr: Base DataModule.
docstr: Split into train, val, test, and set dims.
  Should assign `torch Dataset` objects to self.data_train, self.data_val, and optionally self.data_test.
code: def setup(self, stage=None):
      """
      Split into train, val, test, and set dims.
      Should assign `torch Dataset` objects to self.data_train, self.data_val, and optionally self.data_test.
      """
      self.data_train = None
      self.data_val = None
      self.data_test = None
  
file_path: DeepKE/src/deepke/relation_extraction/few_shot/dataset/base_data_module.py
imports: from torch.utils.data import DataLoader
  from torch import nn
label_desc: Use image node_id 5 for calling the BaseDataModule obj's underlying member method code with example usage: obj.setup(stage) without return types