Installing any or multiple versions of Python on Ubuntu is simple.
First of all install some dependencies:
sudo apt-get install build-essential sudo apt-get install libreadline5-dev libncursesw5 libssl-dev libsqlite3-dev tk-dev libgdbm-dev libc6-dev libc6-dev libbz2-de
cd Downloads wget http://python.org/ftp/python/2.7.3/Python-2.7.3.tgz
Extract and change directory to: ::
Install via building: ::
./configure make sudo make install # This will make it to the default installation, use `altinstall` instead to keep the default if desired.