Issue #22885: Fixed arbitrary code execution vulnerability in the dumbdbm
module.  Original patch by Claudiu Popa.
diff --git a/Lib/test/test_dumbdbm.py b/Lib/test/test_dumbdbm.py
index 6f5324f..6520efd 100644
--- a/Lib/test/test_dumbdbm.py
+++ b/Lib/test/test_dumbdbm.py
@@ -160,6 +160,14 @@
             self.assertEqual(expected, got)
             f.close()
 
+    def test_eval(self):
+        with open(_fname + '.dir', 'w') as stream:
+            stream.write("str(__import__('sys').stdout.write('Hacked!')), 0\n")
+        with test_support.captured_stdout() as stdout:
+            with self.assertRaises(ValueError):
+                dumbdbm.open(_fname).close()
+            self.assertEqual(stdout.getvalue(), '')
+
     def tearDown(self):
         _delete_files()