def METHOD_NAME():
    region = "ap-northeast-1"
    id_1 = add_servers_to_region_boto3(EXAMPLE_AMI_ID, 1, region)[0].id
    id_2 = add_servers_to_region_boto3(EXAMPLE_AMI_ID2, 1, region)[0].id
    client = boto3.client("ec2", region_name=region)
    instances = retrieve_all_instances(client)
    instance1 = [i for i in instances if i["InstanceId"] == id_1][0]
    assert instance1["ImageId"] == EXAMPLE_AMI_ID
    instance2 = [i for i in instances if i["InstanceId"] == id_2][0]
    assert instance2["ImageId"] == EXAMPLE_AMI_ID2