Fix for bug 4360 "SystemError when method has both super() & closure".  Patch
by amaury.forgeotdarc and reviewed by brett.cannon.

Also add release notes about the known problems with the email package.
diff --git a/Lib/test/test_super.py b/Lib/test/test_super.py
index 5594b11..5287402 100644
--- a/Lib/test/test_super.py
+++ b/Lib/test/test_super.py
@@ -70,6 +70,17 @@
         e = E()
         self.assertEqual(e.cm(), (e, (E, (E, (E, 'A'), 'B'), 'C'), 'D'))
 
+    def testSuperWithClosure(self):
+        # Issue4360: super() did not work in a function that
+        # contains a closure
+        class E(A):
+            def f(self):
+                def nested():
+                    self
+                return super().f() + 'E'
+
+        self.assertEqual(E().f(), 'AE')
+
 
 def test_main():
     support.run_unittest(TestSuper)