If you want to do a clean install of Emacs 24.5 =< then you should remove the current version of emacs on your machine and mv your ~/.emacs file to ~/.emacs.bak.
You can choose to use Emacs prelude or Cask. Prelude is probably a better choice.
http://www.wikemacs.org/wiki/Installing_Emacs_on_OS_X
https://github.com/bbatsov/prelude
Check out the Python support provided by Emacs prelude
https://github.com/bbatsov/prelude/blob/master/modules/doc/prelude-python.md
Emacs Python support
https://www.emacswiki.org/emacs/PythonProgrammingInEmacs
http://reinout.vanrees.org/weblog/2010/05/11/pep8-pyflakes-emacs.html
https://github.com/bbatsov/prelude/pull/667
http://www.memonic.com/user/pneff/folder/python/id/1tCJ
Misc.
https://github.com/bbatsov/prelude/blob/master/modules/doc/README.md
https://github.com/bbatsov/zenburn-emacs
https://github.com/ryzzn/zenburn-emacs
http://ergoemacs.org/emacs/elisp.html
You can choose to use Emacs prelude or Cask. Prelude is probably a better choice.
# Setting up emacs from scratch on OSX
mv ~/.emacs ~/.emacs.bak
# install Emacs
http://www.wikemacs.org/wiki/Installing_Emacs_on_OS_X
brew update
sudo rm /usr/bin/emacs
sudo rm -rf /usr/share/emacs
brew install emacs --with-cocoa
# install Emacs prelude
https://github.com/bbatsov/prelude
curl -L https://git.io/epre | sh
https://github.com/bbatsov/prelude/blob/master/modules/doc/prelude-python.md
Emacs Python support
https://www.emacswiki.org/emacs/PythonProgrammingInEmacs
http://reinout.vanrees.org/weblog/2010/05/11/pep8-pyflakes-emacs.html
https://github.com/bbatsov/prelude/pull/667
http://www.memonic.com/user/pneff/folder/python/id/1tCJ
Misc.
https://github.com/bbatsov/prelude/blob/master/modules/doc/README.md
https://github.com/bbatsov/zenburn-emacs
https://github.com/ryzzn/zenburn-emacs
http://ergoemacs.org/emacs/elisp.html
