Install Python3 + pip on i686 and x86_64 Chromebook without using crouton

0) Switch to developer mode
Reboot pressing Esc+Refresh+Power -- > Confirm developer mode
Now each time Chromebook starts, press Ctrl+D to skip waiting time on a white screen

0.1) Open terminal : Ctrl+Alt+T

1) Install Chromebrew ( Homepage)
wget -q -O - https://raw.github.com/skycocker/chromebrew/master/install.sh | bash

2) Make root partition writable with this script:
DennisLfromGA / rw-rootfs

3) Install pip downloading source from here Pip Homepage and using this command:
tar xzf pip*
cd pip*/
sudo python setup.py install

You can now use pip to install various packages (eg. sudo pip install xslxwriter)
Enjoy Python on your Chromebook!!
PS: you can use Chromebook shell to launch a .py file and use Text as simple code editor