def METHOD_NAME(token_client, organizer, event, taxrule):
    resp = token_client.patch(
        '/api/v1/organizers/{}/events/{}/taxrules/{}/'.format(organizer.slug, event.slug, taxrule.pk),
        {
            "custom_rules": [
                {"foo": "bar"}
            ]
        },
        format='json'
    )
    assert resp.status_code == 400
    assert resp.data["custom_rules"][0].startswith(
        "Your set of rules is not valid. Error message: 'country' is a required property"
    )