remove `from __future__ import print_function`

[junkmd]

The from __future__ import print_function will no longer be needed if only Python 3 is supported.

The following should be removed;

PS ...\comtypes> git log -1 --pretty=%H
00f231784f3ac7da83196e1c85095df6290d5b9f
PS ...\comtypes> Get-ChildItem -Path .\comtypes -Recurse | Select-String -SimpleMatch "from __future__ import print_function"  

comtypes\shelllink.py:1:from __future__ import print_function
comtypes\client\_events.py:1:from __future__ import print_function
comtypes\client\_generate.py:1:from __future__ import print_function
comtypes\test\find_memleak.py:1:from __future__ import print_function
comtypes\test\test_agilent.py:5:from __future__ import print_function
comtypes\test\test_createwrappers.py:1:from __future__ import print_function
comtypes\test\test_excel.py:2:from __future__ import print_function
comtypes\test\test_variant.py:1:from __future__ import print_function
comtypes\test\__init__.py:3:from __future__ import print_function
comtypes\tools\codegenerator.py:3:from __future__ import print_function
comtypes\tools\tlbparser.py:1:from __future__ import print_function