          insert(node, 8)
          insert(node, 1)
          insert(node, 3)
  
          with captured_output() as (out, err):
              in_order_traversal(node, sys.stdout.write)
              assert_equal(out.getvalue().strip(), '12358')
  
          with captured_output() as (out, err):
              pre_order_traversal(node, sys.stdout.write)
              assert_equal(out.getvalue().strip(), '52138')
  
 
</s> remove         with captured_output() as (out, err):
            pre_order_traversal(node, sys.stdout.write)
            assert_equal(out.getvalue().strip(), '52138')
 </s> add         pre_order_traversal(node, self.results.add_result)
        assert_equal(str(self.results), "[5, 2, 1, 3, 8]")
        self.results.clear_results() </s> remove         with captured_output() as (out, err):
            post_order_traversal(node, sys.stdout.write)
            assert_equal(out.getvalue().strip(), '13285')
 </s> add         post_order_traversal(node, self.results.add_result)
        assert_equal(str(self.results), "[1, 3, 2, 8, 5]")
        self.results.clear_results() </s> remove         with captured_output() as (out, err):
            in_order_traversal(node, sys.stdout.write)
            assert_equal(out.getvalue().strip(), '12345')
 </s> add         in_order_traversal(node, self.results.add_result)
        assert_equal(str(self.results), "[1, 2, 3, 4, 5]")
        self.results.clear_results() </s> remove         with captured_output() as (out, err):
            pre_order_traversal(node, sys.stdout.write)
            assert_equal(out.getvalue().strip(), '12345')
 </s> add         pre_order_traversal(node, self.results.add_result)
        assert_equal(str(self.results), "[1, 2, 3, 4, 5]")
        self.results.clear_results() </s> remove         with captured_output() as (out, err):
            post_order_traversal(node, sys.stdout.write)
            assert_equal(out.getvalue().strip(), '54321')
 </s> add         post_order_traversal(node, self.results.add_result)
        assert_equal(str(self.results), "[5, 4, 3, 2, 1]")
        in_order_traversal(node, self.results.add_result)
        assert_equal(str(self.results), "[1, 2, 3, 5, 8]")
        self.results.clear_results()
          insert(node, 8)
          insert(node, 1)
          insert(node, 3)
  
        in_order_traversal(node, self.results.add_result)
        assert_equal(str(self.results), "[1, 2, 3, 5, 8]")
        self.results.clear_results()
        in_order_traversal(node, self.results.add_result)
        assert_equal(str(self.results), "[1, 2, 3, 5, 8]")
        self.results.clear_results()
        in_order_traversal(node, self.results.add_result)
        assert_equal(str(self.results), "[1, 2, 3, 5, 8]")
        self.results.clear_results()
  
          with captured_output() as (out, err):
              pre_order_traversal(node, sys.stdout.write)
              assert_equal(out.getvalue().strip(), '52138')
  
keep keep keep keep replace replace replace keep keep keep keep keep
 Reworked tree dfs unit tests. 
graphs_trees/tree_dfs/test_dfs.py