code: def test_brandes_erlebach_book():
      # Figure 1 chapter 7: Connectivity
      # http://www.informatik.uni-augsburg.de/thi/personen/kammer/Graph_Connectivity.pdf
      G = nx.Graph()
      G.add_edges_from(
          [
              (1, 2),
              (1, 3),
              (1, 4),
              (1, 5),
              (2, 3),
              (2, 6),
              (3, 4),
              (3, 6),
              (4, 6),
              (4, 7),
              (5, 7),
              (6, 8),
              (6, 9),
              (7, 8),
              (7, 10),
              (8, 11),
              (9, 10),
              (9, 11),
              (10, 11),
          ]
      )
      for flow_func in flow_funcs:
          kwargs = {"flow_func": flow_func}
          errmsg = f"Assertion failed in function: {flow_func.__name__}"
          # edge cutsets
          assert 3 == len(
              nx.minimum_edge_cut(G, 1, 11, **kwargs)
          ), errmsg
          edge_cut = nx.minimum_edge_cut(G, **kwargs)
          # Node 5 has only two edges
          assert 2 == len(edge_cut), errmsg
          H = G.copy()
          H.remove_edges_from(edge_cut)
          assert not nx.is_connected(H), errmsg
          # node cuts
          assert {6, 7} == minimum_st_node_cut(
              G, 1, 11, **kwargs
          ), errmsg
          assert {6, 7} == nx.minimum_node_cut(
              G, 1, 11, **kwargs
          ), errmsg
          node_cut = nx.minimum_node_cut(G, **kwargs)
          assert 2 == len(node_cut), errmsg
          H = G.copy()
          H.remove_nodes_from(node_cut)
          assert not nx.is_connected(H), errmsg
  
imports: import pytest
  import networkx
  from networkx.algorithms import flow
  from networkx.algorithms.connectivity import minimum_st_edge_cut, minimum_st_node_cut
  from networkx.utils import arbitrary_element
label_desc: Use image node_id 3 for calling a global function with example usage: test_brandes_erlebach_book() without return types