There are many ways to install Ansible inside virtualenv on CentOS7, I would like to show now a very simple variant. Important are actually the CentOS packages at the beginning.

Steps

# install needed packages
$ yum install -y python-setuptools python-devel openssl-devel libffi-devel

# install pip
$ easy_install pip

# install virtualenv
$ pip install virtualenv

# create and activate virtualenv
$ virtualenv .env && . .env/bin/activate

# install latest ansible
(.env) [demo@centos7 ~]$ pip install ansible

# show python packages
(.env) [demo@centos7 ~]$ pip freeze
ansible==2.3.1.0
asn1crypto==0.22.0
bcrypt==3.1.3
cffi==1.10.0
cryptography==1.9
enum34==1.1.6
idna==2.5
ipaddress==1.0.18
Jinja2==2.9.6
MarkupSafe==1.0
paramiko==2.2.1
pyasn1==0.2.3
pycparser==2.17
pycrypto==2.6.1
PyNaCl==1.1.2
PyYAML==3.12
six==1.10.0

# exit virtualenv
(.env) [demo@centos7 ~]$ deactivate

it can be so easy 😉