def assumed_role_to_principle(assumed_role_arn):
    """Return role ARN from assumed role ARN."""
    arn_split = assumed_role_arn.split(":")
    arn_split[2] = "iam"
    base_arn = ":".join(arn_split[:5]) + ":role/"
    return base_arn + assumed_role_arn.split("/")[1]