Dynamic inventory

Download ec2.py from here. Save it in your Ansible root folder.

Edit ansible.cfg as follows:

...
inventory = ./ec2.py
...

Your playbook host must be as follows:

...
hosts: "{{ variable_host | default('tag_tfplayer_vpninstance') }}"
...

Run the playbook:

ansible-playbook playbooks/vpn.yml \
  --extra-vars "variable_host=tag_tfplayer_vpninstance"

variable_host is the EC2 instance tag. In this example the tag name is tfplayer and the tag content is vpninstance.