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
```
queue_url = req_data.get('QueueUrl')
    if queue_url:
        return queue_url[0]
    url = config.TEST_SQS_URL
    if headers.get('Host'):
        url = 'http%s://%s' % ('s' if config.USE_SSL else '', headers['Host'])
    queue_url = '%s%s' % (url, path.partition('?')[0])
    return queue_url
def _add_queue_attributes(path, req_data, content_str, headers):
    flags = re.MULTILINE | re.DOTALL
    queue_url = _queue_url(path, req_data, headers)
    requested_attributes = _format_attributes_names(req_data)
    regex = r'(.*<GetQueueAttributesResult>)(.*)(</GetQueueAttributesResult>.*)'
    attrs = re.sub(regex, r'\2', content_str, flags=flags)
    for key, value in QUEUE_ATTRIBUTES.get(queue_url, {}).items():
        if (not requested_attributes or requested_attributes.intersection({'All', key})) and \
                not re.match(r'<Name>\s*%s\s*</Name>' % key, attrs, flags=flags):
            attrs += '<Attribute><Name>%s</Name><Value>%s</Value></Attribute>' % (key, value)
    content_str = (re.sub(regex, r'\1', content_str, flags=flags) +
                   attrs + re.sub(regex, r'\3', content_str, flags=flags))
    return content_str
class ProxyListenerSQS(ProxyListener):
    def forward_request(self, method, path, data, headers):