virtual-env-setup

In Fedora/CentOS/Red Hat use the following to download pip
	yum install python-pip
In Ubuntu/debian use the following
	sudo apt-get install python-pip


Then use pip to install virtualenv
	sudo pip install virtualenv


Now download the source of required python version.
Then compile it and install it.
	tar -zxvf Python-2.7.5.tgz
	cd Python-2.7.5
	./configure --prefix=<folder to install>
	make
	make install


Now create a Folder to store virtual environments.
	mkdir -p ~/ENV
Then create a new virtual environment in this environment.
	cd ~/ENV
	virtualenv --python=<the place you saved new python> new_env


A "new_env" folder will be created in ~/ENV
To access the virtual environment activate the environment.
	cd ~/ENV/new_env/bin
	source activate


Then you will see your command prompt will change with a bracket containing "new_env" in it.
Now check the python version.
You will find that the new python version is the default python in this environment.


Update setuptools
	easy_install -U setuptools


Here you can install any python library with "pip"
	pip install <library name>
That installation will only remain inside the virtual environment.


After you finish and when you want to exit the virtual environment deactivate it using following command.
	deactivate