bpo-46431: use raw string for regex in test (GH-30901)

diff --git a/Lib/test/test_exception_group.py b/Lib/test/test_exception_group.py
index bbfce944c17658932ed39a6eae2d5220588a8d15..b7b53bb2f0ecef10e37629fa040dfda794fd7f4a 100644 (file)
--- a/Lib/test/test_exception_group.py
+++ b/Lib/test/test_exception_group.py
@@ -22,7 +22,7 @@ class TestExceptionGroupTypeHierarchy(unittest.TestCase):
 
 class BadConstructorArgs(unittest.TestCase):
     def test_bad_EG_construction__too_many_args(self):
-        MSG = 'BaseExceptionGroup.__new__\(\) takes exactly 2 arguments'
+        MSG = r'BaseExceptionGroup.__new__\(\) takes exactly 2 arguments'
         with self.assertRaisesRegex(TypeError, MSG):
             ExceptionGroup('no errors')
         with self.assertRaisesRegex(TypeError, MSG):