code: def setup_class(cls):
      G = nx.Graph()
      G.add_nodes_from([0, 1], fish="one")
      G.add_nodes_from([2, 3], fish="two")
      G.add_nodes_from([4], fish="red")
      G.add_nodes_from([5], fish="blue")
      G.add_edges_from([(0, 1), (2, 3), (0, 4), (2, 5)])
      cls.G = G
  
      D = nx.DiGraph()
      D.add_nodes_from([0, 1], fish="one")
      D.add_nodes_from([2, 3], fish="two")
      D.add_nodes_from([4], fish="red")
      D.add_nodes_from([5], fish="blue")
      D.add_edges_from([(0, 1), (2, 3), (0, 4), (2, 5)])
      cls.D = D
  
      M = nx.MultiGraph()
      M.add_nodes_from([0, 1], fish="one")
      M.add_nodes_from([2, 3], fish="two")
      M.add_nodes_from([4], fish="red")
      M.add_nodes_from([5], fish="blue")
      M.add_edges_from([(0, 1), (0, 1), (2, 3)])
      cls.M = M
  
      S = nx.Graph()
      S.add_nodes_from([0, 1], fish="one")
      S.add_nodes_from([2, 3], fish="two")
      S.add_nodes_from([4], fish="red")
      S.add_nodes_from([5], fish="blue")
      S.add_edge(0, 0)
      S.add_edge(2, 2)
      cls.S = S
  
      N = nx.Graph()
      N.add_nodes_from([0, 1], margin=-2)
      N.add_nodes_from([2, 3], margin=-2)
      N.add_nodes_from([4], margin=-3)
      N.add_nodes_from([5], margin=-4)
      N.add_edges_from([(0, 1), (2, 3), (0, 4), (2, 5)])
      cls.N = N
  
      F = nx.Graph()
      F.add_edges_from([(0, 3), (1, 3), (2, 3)], weight=0.5)
      F.add_edge(0, 2, weight=1)
      nx.set_node_attributes(
          F, dict(F.degree(weight="weight")), "margin"
      )
      cls.F = F
  
      K = nx.Graph()
      K.add_nodes_from([1, 2], margin=-1)
      K.add_nodes_from([3], margin=1)
      K.add_nodes_from([4], margin=2)
      K.add_edges_from([(3, 4), (1, 2), (1, 3)])
      cls.K = K
  
imports: import networkx
label_desc: Use image node_id 1 for calling the BaseTestAttributeMixing obj's underlying member method code with example usage: obj.setup_class(cls) without return types