computer-playbook/roles/cleanup-backups-timer/tasks/main.yml

- name: set service_name to cleanup-backups
  set_fact:
    service_name: "cleanup-backups"
  when: run_once_cleanup_backups_timer is not defined

- name: "include role for systemd-timer for {{service_name}}"
  include_role:
    name: systemd-timer
  vars:
    on_calendar:  "{{on_calendar_cleanup_backups}}"
  when: run_once_cleanup_backups_timer is not defined

- name: run the cleanup_backups_timer tasks once
  set_fact:
    run_once_cleanup_backups_timer: true
  when: run_once_cleanup_backups_timer is not defined