code: def test_custom_motif_networkx():
      import networkx as nx
  
      structure = nx.gnm_random_graph(5, 10, seed=2000)
  
      motif_generator = CustomMotif(structure)
      assert str(motif_generator) == "CustomMotif()"
  
      out = motif_generator()
      assert len(out) == 2
      assert out.num_nodes == 5
      assert out.num_edges == 20
  
imports: import pytest
  import torch
  from torch_geometric.data import Data
  from torch_geometric.datasets.motif_generator import CustomMotif
  from torch_geometric.testing import withPackage
label_desc: Use image node_id 2 for calling a global function with example usage: test_custom_motif_networkx() without return types