how to set up autoscaling for async sagemaker endpoint?

working with an example documented here -> https://github.com/aws/amazon-sagemaker-examples/blob/main/async-inference/Async-Inference-Walkthrough.ipynb. I was able to set up the sagemaker model, config and aync endpoint via lambda, now I'm trying to re-create the stack via terraform. based on the documentation on terraform, i was able to set up the model, config and the endpoint but couldn't find how to go about setting up the auto scaling ( sample code below). is this possible?

client = boto3.client(    "application-autoscaling") 
resource_id = (    "endpoint/" + endpoint_name + "/variant/" + "variant1")  
response = client.register_scalable_target(
    ServiceNamespace="sagemaker",
    ResourceId=resource_id,
    ScalableDimension="sagemaker:variant:DesiredInstanceCount",
    MinCapacity=0,
    MaxCapacity=5,
)
response = client.put_scaling_policy(
    PolicyName="Invocations-ScalingPolicy",
    ServiceNamespace="sagemaker", 
    ResourceId=resource_id,  # Endpoint name
    ScalableDimension="sagemaker:variant:DesiredInstanceCount",  
    PolicyType="TargetTrackingScaling",  # 'StepScaling'|'TargetTrackingScaling'
    TargetTrackingScalingPolicyConfiguration={
        "TargetValue": 5.0,  
SageMakerVariantInvocationsPerInstance
        "CustomizedMetricSpecification": {
            "MetricName": "ApproximateBacklogSizePerInstance",
            "Namespace": "AWS/SageMaker",
            "Dimensions": [{"Name": "EndpointName", "Value": endpoint_name}],
            "Statistic": "Average",
        },
        "ScaleInCooldown": 600,
   ....
    },
)

clean up

response = client.deregister_scalable_target(
    ServiceNamespace='sagemaker',
    ResourceId='resource_id',
    ScalableDimension='sagemaker:variant:DesiredInstanceCount'
)