IAM Policy referenced in the practical


{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Action": [
                "sts:AssumeRole"
            ],
            "Resource": [
                "arn:aws:iam::*:role/AWSCloudFormationStackSetExecutionRole"
            ],
            "Effect": "Allow"
        }
    ]
}