class_docstr: Base class for implementing rooted subgraph transformations.
class_docstr_tok: ["Base","class","for","implementing","rooted","subgraph","transformations","."]
code: def extract(
      self,
      data: Data,
  ) -> Tuple[Tensor, Tensor, Tensor, Tensor, Tensor]:
      # Returns the tuple:
      # :obj:`(sub_edge_index, n_id, e_id, n_sub_batch, e_sub_batch)`
      # of the :class:`RootedSubgraphData` object.
      pass
  
imports: import copy
  from abc import ABC, abstractmethod
  from typing import Any, Tuple
  import torch
  from torch import Tensor
  from torch_geometric.data import Data
  from torch_geometric.transforms import BaseTransform
  from torch_geometric.utils import to_torch_csc_tensor
label_desc: Use image node_id 1 for calling the RootedSubgraph obj's underlying member method code with example usage: obj.extract(data) without return types