added exercise 3

tests/test_ex3.py

@@ -0,0 +1,20 @@
+import unittest
+
+from ex3_cards import tauntScore
+
+
+class MyTestCase(unittest.TestCase):
+    def test_simple1(self):
+        self.assertEqual(
+            tauntScore([1, 3, 2, 2]),
+            5
+        )
+    def test_simple2(self):
+        self.assertEqual(
+            tauntScore([1, 3, 45, 12, 2, 12]),
+            58
+        )
+
+
+if __name__ == '__main__':
+    unittest.main()