----- Debug task: -------

- debug:
    msg:
      test1: "{{ '' | default(None, true) | to_json }}"
      test2: null

------ Output: -----------

ok: [127.0.0.1] => {
    "msg": {
        "test1": "null",
        "test2": null
    }
}

----- Actual task: -------

- kubernetes.core.k8s:
    state: present
    definition:
      kind: ResourceQuota
      apiVersion: v1
      metadata:
        name: compute-resources
        namespace: deleteme
      spec:
        hard:
          # Should either be omitted or a raw null
          limits.cpu: "{{ None if (query('k8s', kind='ResourceQuota', resource_name='compute-resources', namespace='deleteme') | length > 0) else omit }}"
          pods: 6