code: def test_default_flow_function_karate_club_graph(self):
      G = nx.karate_club_graph()
      nx.set_edge_attributes(G, 1, "capacity")
      T = nx.gomory_hu_tree(G)
      assert nx.is_tree(T)
      for u, v in combinations(G, 2):
          cut_value, edge = self.minimum_edge_weight(T, u, v)
          assert nx.minimum_cut_value(G, u, v) == cut_value
  
file_path: networkx/networkx/algorithms/flow/tests/test_gomory_hu.py
imports: from itertools import combinations
  import pytest
  import networkx
  from networkx.algorithms.flow import boykov_kolmogorov, dinitz, edmonds_karp, preflow_push, shortest_augmenting_path
label_desc: Use image node_id 3 for calling the TestGomoryHuTree obj's underlying member method code with example usage: obj.test_default_flow_function_karate_club_graph() without return types