Core and Builtins
-----------------
+- Issue #15578: Correctly incref the parent module while importing.
+
- Issue #26307: The profile-opt build now applys PGO to the built-in modules.
- Issue #27870: A left shift of zero by a large integer no longer attempts
- Add Py3k warnings for parameter names in parentheses.
-- Issue #15578: Correctly incref the parent module while importing.
-
- Issue #7362: Give a proper error message for ``def f((x)=3): pass``.
- Issue #7085: Fix crash when importing some extensions in a thread on MacOSX