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We have been trying to setup s3 and sqs on local stack. What we are trying to do is any object uploaded to s3 sqs queue needs to be notified. Find below bunch commands used. 

```
aws --endpoint-url=http://localhost:4572 s3 mb s3://march
aws --endpoint-url=http://localhost:4576 sqs create-queue --queue-name march
aws --endpoint-url=http://localhost:4572 s3api put-bucket-notification-configuration --bucket march --notification-configuration file://notification.json
aws --endpoint-url=http://localhost:4572 s3 cp test.csv s3://march
aws --endpoint-url=http://localhost:4576 sqs receive-message --queue-url http://localhost:4576/queue/march
```
notification.json content
```
{
  "QueueConfigurations": [
    {
      "QueueArn": "http://localstack:4576/queue/march",
        "Events": [
          "s3:ObjectCreated:*"
        ]
    }
  ]
}
```

Is there anything missing in my above steps? Is this a know issue?
"""Add Last-Modified header with current time
    (if the response content is an XML containing <LastModified>, add that instead)"""
    time_format = '%a, %d %b %Y %H:%M:%S GMT'  
    try:
        if content:
            last_modified_str = re.findall(r'<LastModified>(.*)</LastModified>', content)
            if last_modified_str:
                last_modified_str = last_modified_str[0]
                last_modified_time_format = dateutil.parser.parse(last_modified_str).strftime(time_format)
                response.headers['Last-Modified'] = last_modified_time_format
    except TypeError as err:
        LOGGER.debug('No parsable content: %s' % err)
    except ValueError as err:
        LOGGER.error('Failed to parse LastModified: %s' % err)
    except Exception as err:
        LOGGER.error('Caught generic exception (parsing LastModified): %s' % err)
    
    try:
        if response.headers.get('Last-Modified', '') == '':
            response.headers['Last-Modified'] = datetime.datetime.now().strftime(time_format)
    except Exception as err:
        LOGGER.error('Caught generic exception (setting LastModified header): %s' % err)
def append_list_objects_marker(method, path, data, response):