code: def setup_method(self):
      self.Graph = MultiGraphSubClass
      # build K3
      self.k3edges = [(0, 1), (0, 2), (1, 2)]
      self.k3nodes = [0, 1, 2]
      self.K3 = self.Graph()
      self.K3._adj = self.K3.adjlist_outer_dict_factory(
          {
              0: self.K3.adjlist_inner_dict_factory(),
              1: self.K3.adjlist_inner_dict_factory(),
              2: self.K3.adjlist_inner_dict_factory(),
          }
      )
      self.K3._pred = {0: {}, 1: {}, 2: {}}
      for u in self.k3nodes:
          for v in self.k3nodes:
              if u != v:
                  d = {0: {}}
                  self.K3._adj[u][v] = d
                  self.K3._adj[v][u] = d
      self.K3._node = self.K3.node_dict_factory()
      self.K3._node[0] = self.K3.node_attr_dict_factory()
      self.K3._node[1] = self.K3.node_attr_dict_factory()
      self.K3._node[2] = self.K3.node_attr_dict_factory()
  
imports: from collections import UserDict
  import pytest
  import networkx
  from networkx.utils import edges_equal
  from .test_graph import BaseAttrGraphTester
  from .test_graph import TestGraph
label_desc: Use image node_id 1 for calling the TestMultiGraphSubclass obj's underlying member method code with example usage: obj.setup_method() without return types