added too many args test

rpn.py

@@ -14,6 +14,7 @@ def calculate(arg):
             elif token == '-':
                 result = val1 - val2
             stack.append(result)
+    
     return stack[0]
     
             

test_rpn.py

@@ -8,3 +8,6 @@ class TestBasics(unittest.TestCase):
     def test_subtract(self):
         result = rpn.calculate('4 3 -')
         self.assertEqual(1, result)
+    def test_toomany(self):
+        with self.assertRaises(ValueError):
+            result = rpn.calculate('1 2 3 +')