Added binary tree balance check challenge.

graphs_trees/check_balance/test_check_balance.py

@@ -0,0 +1,30 @@
+from nose.tools import assert_equal
+
+
+class TestCheckBalance(object):
+
+    def test_check_balance(self):
+        node = Node(5)
+        insert(node, 3)
+        insert(node, 8)
+        insert(node, 1)
+        insert(node, 4)
+        assert_equal(check_balance(node), True)
+
+        node = Node(5)
+        insert(node, 3)
+        insert(node, 8)
+        insert(node, 9)
+        insert(node, 10)
+        assert_equal(check_balance(node), False)
+
+        print('Success: test_check_balance')
+
+
+def main():
+    test = TestCheckBalance()
+    test.test_check_balance()
+
+
+if __name__ == '__main__':
+    main()