diff --git a/Shunting Yard/tests.py b/Shunting Yard/tests.py
index 10ac523..5925267 100644
--- a/Shunting Yard/tests.py	
+++ b/Shunting Yard/tests.py	
@@ -5,7 +5,7 @@
 
 class MyTestCase(unittest.TestCase):
     def setup(self):
-        self.sol = Solution()
+        self.__sol = Solution()
 
     def test_algo(self):
         self.setup()
@@ -44,4 +44,4 @@ def test_algo(self):
         ]
 
         for expr, expected in test_cases:
-            self.assertEqual(self.sol.infix_to_postfix(expr), expected)
+            self.assertEqual(self.__sol.infix_to_postfix(expr), expected)