code: def test_iter(self):
      revd = [tuple(reversed(e)) for e in self.G.edges]
      expected = sorted(list(self.G.edges) + revd)
      assert sorted(self.dv.edges) == expected
  
imports: import pytest
  import networkx
  from networkx.utils import edges_equal, nodes_equal
label_desc: Use image node_id 6 for calling the TestToDirected obj's underlying member method code with example usage: obj.test_iter() without return types