code: def test_triadic_census():
      """Tests the triadic_census function."""
      G = nx.DiGraph()
      G.add_edges_from(
          ["01", "02", "03", "04", "05", "12", "16", "51", "56", "65"]
      )
      expected = {
          "030T": 2,
          "120C": 1,
          "210": 0,
          "120U": 0,
          "012": 9,
          "102": 3,
          "021U": 0,
          "111U": 0,
          "003": 8,
          "030C": 0,
          "021D": 9,
          "201": 0,
          "111D": 1,
          "300": 0,
          "120D": 0,
          "021C": 2,
      }
      actual = nx.triadic_census(G)
      assert expected == actual
  
imports: import itertools
  from collections import defaultdict
  from random import sample
  import pytest
  import networkx
label_desc: Use image node_id 3 for calling a global function with example usage: test_triadic_census() without return types