def test_copy(self):
        self.simple_t.children[0].length = 1.2
        self.simple_t.children[1].children[0].length = 0.5
        cp = self.simple_t.copy()
        gen = zip(cp.traverse(include_self=True),
                  self.simple_t.traverse(include_self=True))

        for a, b in gen:
            self.assertIsNot(a, b)
            self.assertEqual(a.name, b.name)
            self.assertEqual(a.length, b.length)
:rtype: int
dataset/ETHPy150Open biocore/scikit-bio/skbio/tree/tests/test_tree.py/TreeTests.test_copy--crossover with--dataset/ETHPy150Open algorhythms/LeetCode/173 Binary Search Tree Iterator.py/BSTIterator.next