fix ubuntu intstall python\ code example

Example 1: how to install tar.gz in ubuntu

Download the desired .tar.gz or (.tar.bz2) file
Open Terminal
Extract the .tar.gz or (.tar.bz2) file with the following commands
tar xvzf PACKAGENAME.tar.gz
tar xvjf PACKAGENAME.tar.bz2
Navigate to the extracted folder using cd command
cd PACKAGENAME
Now run the following command to install the tarball
./configure
make
sudo make install

Example 2: how to upgrade python from 2.7 to 2.9 on ubuntu 14.04

git clone https://github.com/pyenv/pyenv.git ~/.pyenv
 git clone https://github.com/pyenv/pyenv-virtualenv.git ~/.pyenv/plugins/pyenv-virtualenv