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
```
""" Extract request data either from query string (for GET) or request body (for POST). """
    if method == 'POST':
        return urlparse.parse_qs(to_str(data))
    elif method == 'GET':
        parsed_path = urlparse.urlparse(path)
        return urlparse.parse_qs(parsed_path.query)
    return {}
def format_message_attributes(data):
    prefix = 'MessageAttribute'
    names = []
    for (k, name) in [(k, data[k]) for k in data if k.startswith(prefix) and k.endswith('.Name')]:
        attr_name = name[0]
        k_id = k.split('.')[1]
        names.append((attr_name, k_id))
    msg_attrs = {}
    for (key_name, key_id) in names:
        msg_attrs[key_name] = {}
        
        attrs = [(k, data[k]) for k in data
                 if k.startswith('{}.{}.'.format(prefix, key_id)) and not k.endswith('.Name')]
        for (attr_k, attr_v) in attrs:
            attr_name = attr_k.split('.')[3]
            msg_attrs[key_name][attr_name[0].lower() + attr_name[1:]] = attr_v[0]
        
        
        
        msg_attrs[key_name]['stringListValues'] = []
        msg_attrs[key_name]['binaryListValues'] = []
    return msg_attrs
def _format_attributes(req_data):