def METHOD_NAME(aggregator, instance):
    instance.update({'opa_url': 'http://fake.tld'})
    c = OpenPolicyAgentCheck('open_policy_agent', {}, [instance])
    # the check should send CRITICAL
    c.check(instance)
    aggregator.assert_service_check('open_policy_agent.health', status=OpenPolicyAgentCheck.CRITICAL)
    aggregator.assert_service_check('open_policy_agent.plugins_health', status=OpenPolicyAgentCheck.CRITICAL)
    aggregator.assert_service_check('open_policy_agent.bundles_health', status=OpenPolicyAgentCheck.CRITICAL)