It is my understanding that setting an environment varialbe `TEST_AWS_ACCOUNT_ID` for localstack sets that as the AWS account for the user in localstack.

However, setting it does not actually change any ARNs. For example:

1. Start localstack using `TEST_AWS_ACCOUNT_ID="111111111111" DEBUG=1 localstack start`
2. Deploy anything with an ARN (in this example I deployed a lambda)
3. Check the ARN. Example output for lambda:
```json
$ awslocal lambda list-functions
{
    "Functions": [
        {
            "FunctionName": "localtest-local-hello",
            "FunctionArn": "arn:aws:lambda:us-east-1:000000000000:function:localtest-local-hello",
            "Runtime": "nodejs10.x",
            "Role": "test_role",
            "Handler": "handler.hello",
            "CodeSize": 3077,
            "Description": "",
            "Timeout": 6,
            "MemorySize": 1024,
            "LastModified": "2019-11-06T06:43:53.451+0000",
            "CodeSha256": "V77gR13o90ET7+XquXBBc3Rxr1qDu1bE7S+A0Wbx5ys=",
            "Version": "$LATEST",
            "TracingConfig": {
                "Mode": "PassThrough"
            },
            "RevisionId": "3d4ed679-c1a9-4b7e-ad9e-f27e8543c5e9"
        }
    ]
}
```

ARN is still 000000000000
client = aws_stack.connect_to_service('cloudformation')
    try:
        result = client.describe_stack_resource(StackName=stack_name, LogicalResourceId=logical_resource_id)
        return result['StackResourceDetail']
    except Exception as e:
        LOG.warning('Unable to get details for resource "%s" in CloudFormation stack "%s": %s' %
                    (logical_resource_id, stack_name, e))
def retrieve_resource_details(resource_id, resource_status, resources, stack_name):
    resource = resources.get(resource_id)
    resource_id = resource_status.get('PhysicalResourceId') or resource_id
    if not resource:
        resource = {}
    resource_type = get_resource_type(resource)
    resource_props = resource.get('Properties')
    try:
        if resource_type == 'Lambda::Function':
            resource_id = resource_props['FunctionName'] if resource else resource_id
            return aws_stack.connect_to_service('lambda').get_function(FunctionName=resource_id)