code: def test_christofides_hamiltonian():
      random.seed(42)
      G = nx.complete_graph(20)
      for u, v in G.edges():
          G[u][v]["weight"] = random.randint(0, 10)
  
      H = nx.Graph()
      H.add_edges_from(pairwise(nx_app.christofides(G)))
      H.remove_edges_from(nx.find_cycle(H))
      assert len(H.edges) == 0
  
      tree = nx.minimum_spanning_tree(G, weight="weight")
      H = nx.Graph()
      H.add_edges_from(pairwise(nx_app.christofides(G, tree)))
      H.remove_edges_from(nx.find_cycle(H))
      assert len(H.edges) == 0
  
imports: import random
  import pytest
  import networkx
  import networkx.algorithms.approximation
label_desc: Use image node_id 1 for calling a global function with example usage: test_christofides_hamiltonian() without return types