def METHOD_NAME(
    self, app, auth_client_header, third_party_user, group_payload
):
    group_payload["groupid"] = "group:23456@thirdparty.com"
    headers = auth_client_header
    headers["X-Forwarded-User"] = third_party_user.userid
    app.post_json("/api/groups", group_payload, headers=headers)
    res = app.post_json(
        "/api/groups", group_payload, headers=headers, expect_errors=True
    )
    assert res.status_code == 409