bpo-44206: Make sure that dict-keys's version is set to zero when value is popped (GH-27542)

Lib/test/test_module.py

@@ -332,6 +332,18 @@ a = A(destroyed)"""
         self.assertFalse("__annotations__" in ann_module4.__dict__)
 
 
+    def test_repeated_attribute_pops(self):
+        # Repeated accesses to module attribute will be specialized
+        # Check that popping the attribute doesn't break it
+        m = ModuleType("test")
+        d = m.__dict__
+        count = 0
+        for _ in range(100):
+            m.attr = 1
+            count += m.attr # Might be specialized
+            d.pop("attr")
+        self.assertEqual(count, 100)
+
     # frozen and namespace module reprs are tested in importlib.