code: def _put_tensor(
      self, tensor: FeatureTensorType, attr: TensorAttr
  ) -> bool:
      index = attr.index
  
      # None indices define the obvious index:
      if index is None:
          index = torch.arange(0, tensor.shape[0])
  
      # Store the index:
      assert isinstance(index, Tensor)
      assert isinstance(tensor, Tensor)
      self.store[self.key(attr)] = (index, tensor)
  
      return True
  
file_path: pytorch_geometric/torch_geometric/testing/feature_store.py
imports: from typing import Dict, List, Optional, Tuple
  import torch
  from torch import Tensor
  from torch_geometric.data import FeatureStore, TensorAttr
  from torch_geometric.typing import FeatureTensorType
label_desc: Use image node_id 3 for calling the MyFeatureStore obj's underlying member method code with example usage: obj._put_tensor(tensor, attr) and returns: True