Running Ansible tasks in the background

Example:

- name: start collectstatic in the background
  command: "{{ install_root }}/env/bin/python manage.py collectstatic --noinput -v 0"
  args:
    chdir: "{{ install_root }}/webapp"
  async: 1000
  poll: 0
  register: collectstatic_bg

################################################################################
#
# PUT TASKS HERE THAT DON'T NEED TO BE RUN BEFORE COLLECTSTATIC CAN START,
# AND THAT WON'T AFFECT THE BACKGROUND COLLECTSTATIC.
#
################################################################################
- name: clean up local tarball
  delegate_to: 127.0.0.1   # Run on localhost
  run_once: yes            # only once
  become: no               # Don't need sudo
  file:
    state: absent
    path: "{{ tarball }}"

- name: migrate
  command: "{{ install_root }}/env/bin/python manage.py migrate --noinput"
  args:
    chdir: "{{ install_root }}/webapp"

- name: install tasks
  command: "{{ install_root }}/env/bin/python manage.py installtasks --traceback"
  args:
    chdir: "{{ install_root }}/webapp"

################################################################################
#
# Check every 'delay' seconds, up to 'retries' times, until collectstatic is done
#
################################################################################
- name: wait for collectstatic to finish
  async_status: jid={{ collectstatic_bg.ansible_job_id }}
  register: job_result
  until: job_result.finished
  retries: 80
  delay: 15

################################################################################
#
# PUT TASKS AFTER THIS THAT CAN'T RUN UNTIL COLLECTSTATIC IS DONE
#
################################################################################