Ansible: How to change Python Version

Question

Trying to use GNS3 to practice ansible script, there is a docker instance called "Network Automation" with built-in ansible. However, it still uses Python 2.7 as the interpreter:

root@Network-Automation:~# ansible --version
ansible 2.7.11
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/root/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python2.7/dist-packages/ansible
  executable location = /usr/bin/ansible
  python version = 2.7.12 (default, Nov 12 2018, 14:36:49) [GCC 5.4.0 20160609]

I understand I can use "ansible-playbook --version -e 'ansible_python_interpreter=/usr/bin/python3'" command to run a playbook with Python version 3, or I can specifiy var within the playbook:

- name: Common package
  hosts: all
  gather_facts: no
  vars:
    ansible_python_interpreter: /usr/bin/python3
  roles:
    - { role: python, tags: [ init, python, common, addusers] }
...
...

However, I would like to have a permanent way to force ansible to use Python3 version. How can I achieve this? Thanks.

Answer 1

Why not use the var directory in your role...

├── defaults
│   └── main.yml
├── files
├── handlers
│   └── main.yml
├── meta
│   └── main.yml
├── README.md
├── tasks
│   └── main.yml
├── templates
├── tests
│   ├── inventory
│   └── test.yml
└── vars
    └── main.yml

in vars/main.yml just add....

---                                                                                                                                                                        
# vars file for XXXX
  ansible_python_interpreter: /usr/bin/python3