sqs.changeMessageVisibility according to [this](https://docs.aws.amazon.com/AWSSimpleQueueService/latest/APIReference/API_ChangeMessageVisibility.html#API_ChangeMessageVisibility_Examples) makes a request directly to the Queue's URL rather than via the SQS Endpoint. (I'm already setting SQS endpoint to LOCALSTACK_HOSTNAME - makes no difference for this call)..

In localstack the queue URL host returned is by default set to the value of HOSTNAME_EXTERNAL, which I'm setting to localstack, but calling this method within a lambda, does not work and I get the error:

```
UnknownEndpoint: Inaccessible host: `localstack'. This service may not be available in the `us-east-1' region. 
```

So, how can I make the queue URL accessible from within a lambda using localstack? Effectively I need to make **http://localstack** accessible from within lambda.

I'm using the following cmd to start localstack:

```
LAMBDA_EXECUTOR=docker-reuse DEBUG=1 LAMBDA_REMOTE_DOCKER=0 DATA_DIR=/tmp/localstack/data HOSTNAME_EXTERNAL=localstack localstack start
```
region_name = extract_region_from_arn(queue_arn)
    queue_name = sqs_queue_name(queue_arn)
    client = connect_to_service('sqs', region_name=region_name)
    response = client.get_queue_url(QueueName=queue_name)
    return response['QueueUrl']
def sqs_receive_message(queue_arn):
    region_name = extract_region_from_arn(queue_arn)
    client = connect_to_service('sqs', region_name=region_name)
    queue_url = get_sqs_queue_url(queue_arn)
    response = client.receive_message(QueueUrl=queue_url)
    return response
def mock_aws_request_headers(service='dynamodb', region_name=None):
    ctype = APPLICATION_AMZ_JSON_1_0
    if service == 'kinesis':
        ctype = APPLICATION_AMZ_JSON_1_1
    elif service == 'sqs':
        ctype = APPLICATION_X_WWW_FORM_URLENCODED
    access_key = get_boto3_credentials().access_key
    region_name = region_name or get_region()
    headers = {
        'Content-Type': ctype,
        'Accept-Encoding': 'identity',
        'X-Amz-Date': '20160623T103251Z',
        'Authorization': ('AWS4-HMAC-SHA256 ' +
            'Credential=%s/20160623/%s/%s/aws4_request, ' +
            'SignedHeaders=content-type;host;x-amz-date;x-amz-target, Signature=1234') % (
                access_key, region_name, service)
    }
    return headers
def dynamodb_get_item_raw(request):