Chromebook Developer Mode
Its possible to get python and idle onto chromebook, but the chromebook must be in developer mode, use crouton to install Ubuntu LTS with XFCE
Steps to turn on Developer Mode on Chromebook are:
Turn off your ChromeBook
Holding Esc + Refresh (F3) buttons while pressing Power button. Then release Power Button.
Your screen will display Recovery screen. Here, press Ctrl+D to turn on Developer mode. Wait for a few minutes.
Download and Install crouton
Download and Install crouton
https://github.com/dnschneid/crouton
Enter the chromeos terminal by press Ctrl+Alt+T
Shell and only works in developer mode
sudo install -Dt /usr/local/bin -m 755 ~/Downloads/crouton
Installing Ubuntu LTS with Xfce
sudo crouton -t xfce
Sudo chroot-enter startxfce4