.. bpo: 23722
.. date: 9790
.. nonce: e8BH5h
.. release date: 2016-12-06
.. section: Core and Builtins

Rather than silently producing a class that doesn't support zero-argument
``super()`` in methods, failing to pass the new ``__classcell__`` namespace
entry up to ``type.__new__`` now results in a ``DeprecationWarning`` and a
class that supports zero-argument ``super()``.

..

.. bpo: 28797
.. date: 9789
.. nonce: _A0_Z5
.. section: Core and Builtins

Modifying the class __dict__ inside the __set_name__ method of a descriptor
that is used inside that class no longer prevents calling the __set_name__
method of other descriptors.

..

.. bpo: 28782
.. date: 9788
.. nonce: foJV_E
.. section: Core and Builtins

Fix a bug in the implementation ``yield from`` when checking if the next
instruction is YIELD_FROM. Regression introduced by WORDCODE (issue #26647).

..

.. bpo: 27030
.. date: 9787
.. nonce: 88FOrz
.. section: Library

Unknown escapes in re.sub() replacement template are allowed again.  But
they still are deprecated and will be disabled in 3.7.

..

.. bpo: 28835
.. date: 9786
.. nonce: Fv7Dr1
.. section: Library

Fix a regression introduced in warnings.catch_warnings(): call
warnings.showwarning() if it was overridden inside the context manager.

..

.. bpo: 27172
.. date: 9785
.. nonce: mVKfLT
.. section: Library

To assist with upgrades from 2.7, the previously documented deprecation of
``inspect.getfullargspec()`` has been reversed. This decision may be
revisited again after the Python 2.7 branch is no longer officially
supported.

..

.. bpo: 26273
.. date: 9784
.. nonce: ilNIWN
.. section: Library

Add new :data:`socket.TCP_CONGESTION` (Linux 2.6.13) and
:data:`socket.TCP_USER_TIMEOUT` (Linux 2.6.37) constants. Patch written by
Omar Sandoval.

..

.. bpo: 24142
.. date: 9783
.. nonce: IrZnFs
.. section: Library

Reading a corrupt config file left configparser in an invalid state.
Original patch by Florian Höch.

..

.. bpo: 28843
.. date: 9782
.. nonce: O7M0LE
.. section: Library

Fix asyncio C Task to handle exceptions __traceback__.

..

.. bpo: 28808
.. date: 9781
.. nonce: A03X6r
.. section: C API

PyUnicode_CompareWithASCIIString() now never raises exceptions.

..

.. bpo: 23722
.. date: 9780
.. nonce: 6HX6fk
.. section: Documentation

The data model reference and the porting section in the What's New guide now
cover the additional ``__classcell__`` handling needed for custom
metaclasses to fully support :pep:`487` and zero-argument ``super()``.

..

.. bpo: 28023
.. date: 9779
.. nonce: 4gzSGp
.. section: Tools/Demos

Fix python-gdb.py didn't support new dict implementation.