#18741: merge with 3.3.

diff --cc Lib/concurrent/futures/process.py
Simple merge

diff --cc Lib/distutils/command/install.py
Simple merge

diff --cc Lib/test/support/__init__.py
Simple merge

diff --cc Lib/unittest/test/test_case.py
Simple merge

diff --cc Lib/unittest/test/test_program.py
Simple merge

diff --cc Lib/xml/etree/ElementTree.py
Simple merge