diff --git a/Lib/test/test_posix.py b/Lib/test/test_posix.py
index 588c869..53a4c5f 100644
--- a/Lib/test/test_posix.py
+++ b/Lib/test/test_posix.py
@@ -1071,7 +1071,7 @@ def test_getgroups(self):
         if sys.platform == 'darwin':
             import sysconfig
             dt = sysconfig.get_config_var('MACOSX_DEPLOYMENT_TARGET') or '10.0'
-            if tuple(int(n) for n in str(dt).split('.')[0:2]) < (10, 6):
+            if tuple(int(n) for n in dt.split('.')[0:2]) < (10, 6):
                 raise unittest.SkipTest("getgroups(2) is broken prior to 10.6")
 
         # 'id -G' and 'os.getgroups()' should return the same