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
```
"""
        Starts a repeating timer that triggers start_idle_container_destroyer_interval every 60 seconds.
        Thus checking for idle containers and destroying them.
        :return: None
        """
        self.idle_container_destroyer()
        threading.Timer(60.0, self.start_idle_container_destroyer_interval).start()
    def get_container_name(self, func_arn):
        """
        Given a function ARN, returns a valid docker container name.
        :param func_arn: The ARN of the lambda function.
        :return: A docker compatible name for the arn.
        """
        return 'localstack_lambda_' + re.sub(r'[^a-zA-Z0-9_.-]', '_', func_arn)
class LambdaExecutorSeparateContainers(LambdaExecutorContainers):
    def __init__(self):
        super(LambdaExecutorSeparateContainers, self).__init__()
        self.next_port = 1
        self.max_port = LAMBDA_API_UNIQUE_PORTS
        self.port_offset = LAMBDA_API_PORT_OFFSET
    def prepare_event(self, environment, event_body):