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
```
func_details = arn_to_lambda.get(arn)
    if not func_details:
        return not_found_error(arn)
    result = {'Tags': func_details.tags}
    return jsonify(result)
@app.route('/<version>/tags/<arn>', methods=['POST'])
def tag_resource(version, arn):
    data = json.loads(request.data)
    tags = data.get('Tags', {})
    if tags:
        func_details = arn_to_lambda.get(arn)
        if not func_details:
            return not_found_error(arn)
        if func_details:
            func_details.tags.update(tags)
    return jsonify({})
@app.route('/<version>/tags/<arn>', methods=['DELETE'])
def untag_resource(version, arn):
    tag_keys = request.args.getlist('tagKeys')
    func_details = arn_to_lambda.get(arn)
    if not func_details:
        return not_found_error(arn)
    for tag_key in tag_keys:
        func_details.tags.pop(tag_key, None)
    return jsonify({})
def serve(port, quiet=True):
    
    LAMBDA_EXECUTOR.startup()
    generic_proxy.serve_flask_app(app=app, port=port, quiet=quiet)