def METHOD_NAME(
    cfngin_context: MockCFNginContext,
) -> None:
    """Test ensure_server_cert_exists already exists."""
    cert_name = "foo"
    arn = f"arn:aws:iam::0123456789012:certification/{cert_name}"
    stub = cfngin_context.add_stubber("iam")
    stub.add_response(
        "get_server_certificate",
        {  # data required by botocore.stub
            "ServerCertificate": {
                "ServerCertificateMetadata": {
                    "Path": "/",
                    "ServerCertificateName": cert_name,
                    "ServerCertificateId": "0" * 16,
                    "Arn": arn,
                },
                "CertificateBody": "0",
            }
        },
        {"ServerCertificateName": cert_name},
    )
    with stub:
        assert ensure_server_cert_exists(cfngin_context, cert_name=cert_name) == {
            "cert_arn": arn,
            "cert_name": cert_name,
            "status": "exists",
        }
    stub.assert_no_pending_responses()