Question

How do I install Ansible using virtualenv?

Answer 1

Depends on which environment you need to install. 

For Mac:

sudo easy_install pip
sudo pip install --upgrade pip
pip install virtualenv

Answer 2

Adding to @Mohit's answer, 

For CentOS and RHEL:

sudo yum install python-virtualenv

For ubuntu:

sudo apt install python-virtualenv

Once you've installed you create a virtual environment

virtualenv myansible

source myansible/bin/activate

Now install ansible

pip install ansible