Issue #25590: Merge rlcompleter change from 3.4 into 3.5

diff --cc Lib/test/test_rlcompleter.py
Simple merge

diff --cc Misc/NEWS
index c766615d7419c6bd4113e86c62e4a72d1963ca89,ec2b4afecd67cc74ed21dd01c9cc4fb9ed14df68..2b312e8f407239fd546a9a0cb7cf65c144915346
--- 1/Misc/NEWS
--- 2/Misc/NEWS
+++ b/Misc/NEWS
@@@ -67,16 -103,13 +67,19 @@@ Core and Builtin
  Library
  -------
  
+ - Issue #25590: In the Readline completer, only call getattr() once per
+   attribute.
+ 
  - Issue #25498: Fix a crash when garbage-collecting ctypes objects created
 -  by wrapping a memoryview.  This was a regression made in 3.4.3.  Based
 +  by wrapping a memoryview.  This was a regression made in 3.5a1.  Based
    on patch by Eryksun.
  
 +- Issue #25584: Added "escape" to the __all__ list in the glob module.
 +
 +- Issue #25584: Fixed recursive glob() with patterns starting with '\*\*'.
 +
 +- Issue #25446: Fix regression in smtplib's AUTH LOGIN support.
 +
  - Issue #18010: Fix the pydoc web server's module search function to handle
    exceptions from importing packages.