code: def to_undirected(  # noqa: F811
      edge_index: Tensor,
      edge_attr: List[Tensor],
      num_nodes: Optional[int] = None,
      reduce: str = "add",
  ) -> Tuple[Tensor, List[Tensor]]:
      pass
  
file_path: pytorch_geometric/torch_geometric/utils/undirected.py
imports: import typing
  from typing import List, Optional, Tuple, Union
  import torch
  from torch import Tensor
  from torch_geometric.typing import OptTensor
  from torch_geometric.utils import coalesce, sort_edge_index
  from torch_geometric.utils.num_nodes import maybe_num_nodes
label_desc: Use image node_id 7 for calling a global function with example usage: to_undirected(edge_index, edge_attr, num_nodes, reduce) without return types