code: def test_to_directed(self):
      G = self.K3
      self.add_attributes(G)
      H = nx.MultiDiGraph(G)
      self.is_shallow_copy(H, G)
      H = G.to_directed()
      self.is_deepcopy(H, G)
  
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 10 for calling the BaseMultiGraphTester obj's underlying member method code with example usage: obj.test_to_directed() without return types