---

- name: install pillow prerequisites for Ubuntu < 14.04
  apt:
    pkg:
    - libjpeg8-dev
    - libtiff4-dev
    - tcl8.5-dev
    - tk8.5-dev
    state: present
    force: yes
  when: ansible_distribution_version is version_compare('14.04', 'lt')

- name: install pillow prerequisites for Ubuntu >= 14.04
  apt:
    pkg:
    - libjpeg8-dev
    - libtiff5-dev
    - tcl8.6-dev
    - tk8.6-dev
    state: present
    force: yes
  when: ansible_distribution_version is version_compare('14.04', 'ge')

- name: install pdf prerequisites for Ubuntu < 18.04
  apt:
    pkg:
      - libssl-dev
    state: present
    force: yes
  when: ansible_distribution_version is version_compare('18.04', 'lt')

- name: install pdf prerequisites for Ubuntu >= 18.04
  apt:
    pkg:
      - libssl1.0-dev
    state: present
    force: yes
  when: ansible_distribution_version is version_compare('18.04', 'ge')

...