code: def test_grid_graph():
      graph_generator = GridGraph(height=10, width=10)
      assert str(graph_generator) == "GridGraph(height=10, width=10)"
  
      data = graph_generator()
      assert len(data) == 2
      assert data.num_nodes == 100
      assert data.num_edges == 784
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_grid_graph() without return types