diff --git a/Lib/test/test_optparse.py b/Lib/test/test_optparse.py
index 3c8c612..7621c24 100644
--- a/Lib/test/test_optparse.py
+++ b/Lib/test/test_optparse.py
@@ -395,6 +395,7 @@
         self.assertRaises(self.parser.remove_option, ('foo',), None,
                           ValueError, "no such option 'foo'")
 
+    @support.impl_detail('Relies on sys.getrefcount', cpython=True)
     def test_refleak(self):
         # If an OptionParser is carrying around a reference to a large
         # object, various cycles can prevent it from being GC'd in