code: def _dgl_idx_to_cugraph_idx(idx, cugraph_gs):
      if not isinstance(idx, dict):
          if len(cugraph_gs.ntypes) > 1:
              raise dgl.DGLError(
                  "Must specify node type when the graph is not homogeneous."
              )
          return idx
      else:
          return {
              k: cugraph_gs.dgl_n_id_to_cugraph_id(n, k)
              for k, n in idx.items()
          }
  
file_path: cugraph/python/cugraph-dgl/cugraph_dgl/dataloading/dataloader.py
imports: from __future__ import annotations
  import os
  import shutil
  import cugraph_dgl
  import cupy
  import cudf
  from cugraph.utilities.utils import import_optional
  from cugraph.gnn import BulkSampler
  from dask.distributed import default_client, Event
  from cugraph_dgl.dataloading import HomogenousBulkSamplerDataset, HeterogenousBulkSamplerDataset
  from cugraph_dgl.dataloading.utils.extract_graph_helpers import create_cugraph_graph_from_edges_dict
label_desc: Use image node_id 3 for calling a global function with example usage: _dgl_idx_to_cugraph_idx(idx, cugraph_gs) and returns: idx, unknown