Issue #20120: Merge with 3.5

diff --cc Misc/NEWS
index db22c2b0a0dca861859359573cfafd7502e2ec5b,2993c66331009fa61325a1d8e7da258c257176f0..a8a3e3a4be66298921740dcab146af703d7ad087
--- 1/Misc/NEWS
--- 2/Misc/NEWS
+++ b/Misc/NEWS
@@@ -10,17 -10,12 +10,23 @@@ Release date: tb
  Core and Builtins
  -----------------
  
+ - Issue #20120: Use RawConfigParser for .pypirc parsing,
+   removing support for interpolation unintentionally added
+   with move to Python 3. Behavior no longer does any
+   interpolation in .pypirc files, matching behavior in Python
+   2.7 and Setuptools 19.0.
+ 
 +- Issue #26249: Memory functions of the :c:func:`PyMem_Malloc` domain
 +  (:c:data:`PYMEM_DOMAIN_MEM`) now use the :ref:`pymalloc allocator <pymalloc>`
 +  rather than system :c:func:`malloc`. Applications calling
 +  :c:func:`PyMem_Malloc` without holding the GIL can now crash: use
 +  ``PYTHONMALLOC=debug`` environment variable to validate the usage of memory
 +  allocators in your application.
 +
 +- Issue #26802: Optimize function calls only using unpacking like
 +  ``func(*tuple)`` (no other positional argument, no keyword): avoid copying
 +  the tuple. Patch written by Joe Jevnik.
 +
  - Issue #26659: Make the builtin slice type support cycle collection.
  
  - Issue #26718: super.__init__ no longer leaks memory if called multiple times.