---
- name: Include distribution specific variables or include sane defaults
  block:
    - name: Include distribution specific variables
      include_vars:
        file: "{{ ansible_distribution | lower }}_{{ ansible_distribution_major_version }}.yml"

  rescue:
    - name: Distribution not supported; including sane defaults...
      include_vars:
        file: __default_packages.yml


- name: "Install base packages for host"
  package:
    name  : "{{ __base_packages }}"
    state : present


...