How to break Ansible

Result

% ansible-playbook test.yml
 [WARNING]: Host file not found: .../homebrew/etc/ansible/hosts

 [WARNING]: provided hosts list is empty, only localhost is available


PLAY [Fuck this shit] **********************************************************

TASK [setup] *******************************************************************
ok: [localhost]

TASK [command] *****************************************************************
changed: [localhost]

TASK [debug] *******************************************************************
fatal: [localhost]: FAILED! => {"failed": true, "msg": "{u'cmd': u\"echo '{{}}' > /dev/null\", u'end': u'2017-07-02 16:35:55.922241', u'stdout': u'', u'changed': True, u'start': u'2017-07-02 16:35:55.914838', u'delta': u'0:00:00.007403', u'stderr': u'', u'rc': 0, 'stdout_lines': [], u'warnings': []}: template error while templating string: Expected an expression, got 'end of print statement'. String: echo '{{}}' > /dev/null"}
        to retry, use: --limit @.../test.retry

PLAY RECAP *********************************************************************
localhost                  : ok=2    changed=1    unreachable=0    failed=1

test.yml

- name: Fuck this shit
  hosts: localhost
  tasks:
    - shell: echo '{{"{{}}"}}' > /dev/null
      register: foo
    - debug: msg="{{ foo.stdout }}"