Issue #27369: Merge test_pyexpat from 3.5

diff --cc Misc/NEWS
index b9bd9496d5355261609470eba54816c37163deec,835304b5f986034f8ed2d0c4047f5c2cdab119ce..685ffa3e40a9e33b7d5ae39832c391adf365db04
--- 1/Misc/NEWS
--- 2/Misc/NEWS
+++ b/Misc/NEWS
@@@ -2,22 -2,10 +2,28 @@@
  Python News
  +++++++++++
  
 -What's New in Python 3.5.3 release candidate 1?
 -===============================================
 +What's New in Python 3.6.0 alpha 4
 +==================================
  
 -Release date: TBA
 +*Release date: XXXX-XX-XX*
 +
 +Core and Builtins
 +-----------------
 +
 +Library
 +-------
 +
++Tests
++-----
++
++- Issue #27369: In test_pyexpat, avoid testing an error message detail that
++  changed in Expat 2.2.0.
++
 +
 +What's New in Python 3.6.0 alpha 3
 +==================================
 +
 +*Release date: 2016-07-11*
  
  Core and Builtins
  -----------------