Make this test a bit harder

test/tests/descr_selfdelete.py

+import sys
+
 class C(object):
     def __delattr__(self, attr):
         print "__delattr__"
         del C.__delattr__
+        sys._clear_type_cache()
 c = C()
 del c.a
 try:
@@ -13,6 +16,7 @@ class C(object):
     def __getattr__(self, attr):
         print "__getattr__"
         del C.__getattr__
+        sys._clear_type_cache()
         return attr
 c = C()
 print c.a
@@ -25,9 +29,31 @@ class C(object):
     def __setattr__(self, attr, val):
         print "__setattr__", attr, val
         del C.__setattr__
+        sys._clear_type_cache()
 c = C()
 c.a = 1
 try:
     c.a = 2
 except Exception as e:
     print e
+
+
+class D(object):
+    def __get__(self, obj, type):
+        print "D.__get__"
+        del D.__get__
+        sys._clear_type_cache()
+        return 1
+
+    def __set__(self, obj, value):
+        print "D.__set__"
+        del D.__set__
+        sys._clear_type_cache()
+
+C.x = D()
+c = C()
+c.x = 0
+print c.x
+c.x = 0
+print c.x
+