1. python 2.6 =>
2. pip
3. ansible
4. boto

1. pip install ansible
2. pip install boto
3. create credentials file called credentials.yml to include AWS keys

    ---
    ec2_access_key: "--REMOVED--"
    ec2_secret_key: "--REMOVED--"

http://docs.ansible.com/ansible/intro_dynamic_inventory.html#example-aws-ec2-external-inventory-script

with static hosts file use:

ansible-playbook -i hosts aws-playbook.yml

With dynamic inventory use:

ansible-playbook -i ec2.py aws-playbook.yml

if you encrypted the credentials file with ansible vault use following line.

ansible-playbook -i ec2.py aws-playbook.yml --ask-vault-pass

if you want debug messages during runs add -vvvv