<!-- Love localstack? Please consider supporting our collective:
👉  https://opencollective.com/localstack/donate -->

Under utils/common.py, 

TIMESTAMP_FORMAT_MILLIS = '%Y-%m-%dT%H:%M:%S.%fZ'

The %f produces time with microseconds, for example: 2020-03-18T19:43:18.115783Z.


However, when interacting the AWS s3 and sns apis, I receive DateTimes like this:

2020-03-02T22:32:13.240Z
i.e. milliseconds. 

This seems like a simple change to the utils. TIMESTAMP_FORMAT_MILLIS is named as if it should be millis as well. This is seems like a simple change. Is there a reason it should be microseconds?
if method != 'GET' or path != '/':
        return
    response._content = re.sub(r'([0-9])</CreationDate>', r'\1Z</CreationDate>', to_str(response._content))
def fix_etag_for_multipart(data, headers, response):
    
    if headers.get(CONTENT_SHA256_HEADER) == STREAMING_HMAC_PAYLOAD:
        try:
            if b'chunk-signature=' not in to_bytes(data):
                return
            correct_hash = md5(strip_chunk_signatures(data))
            tags = r'<ETag>%s</ETag>'
            pattern = r'(&#34;)?([^<&]+)(&#34;)?'
            replacement = r'\g<1>%s\g<3>' % correct_hash
            response._content = re.sub(tags % pattern, tags % replacement, to_str(response.content))
            if response.headers.get('ETag'):
                response.headers['ETag'] = re.sub(pattern, replacement, response.headers['ETag'])
        except Exception:
            pass
def remove_xml_preamble(response):