keystone/api-ref/source/v3/samples/admin/policy-create-response.json

{
    "policy": {
        "links": {
            "self": "http://example.com/identity/v3/policies/88f5b83f8f8e41daba4c25eed1a7bbc6"
        },
        "blob": "{'foobar_user': 'role:compute-user'}",
        "type": "application/json",
        "id": "88f5b83f8f8e41daba4c25eed1a7bbc6"
    }
}