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
```
return '%s:%s' % (self.region, self.prefix)
PREDEFINED_ENVIRONMENTS = {
    ENV_DEV: Environment(region=REGION_LOCAL, prefix=ENV_DEV)
}
def get_environment(env=None, region_name=None):
    """
    Return an Environment object based on the input arguments.
    Parameter `env` can be either of:
        * None (or empty), in which case the rules below are applied to (env = os.environ['ENV'] or ENV_DEV)
        * an Environment object (then this object is returned)
        * a string '<region>:<name>', which corresponds to Environment(region='<region>', prefix='<prefix>')
        * the predefined string 'dev' (ENV_DEV), which implies Environment(region='local', prefix='dev')
        * a string '<name>', which implies Environment(region=DEFAULT_REGION, prefix='<name>')
    Additionally, parameter `region_name` can be used to override DEFAULT_REGION.
    """
    if not env:
        if 'ENV' in os.environ:
            env = os.environ['ENV']
        else:
            env = ENV_DEV
    elif not is_string(env) and not isinstance(env, Environment):
        raise Exception('Invalid environment: %s' % env)
    if is_string(env):
        env = Environment.from_string(env)
    if region_name:
        env.region = region_name
    if not env.region:
        raise Exception('Invalid region in environment: "%s"' % env)
    return env
def is_local_env(env):