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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?
host = headers['host']
    for pattern in [common_pattern, dualstack_pattern, legacy_patterns]:
        match = pattern.match(host)
        if match:
            bucket_name = match.groups()[0]
            break
    
    
    return normalize_bucket_name(bucket_name)
def handle_notification_request(bucket, method, data):
    response = Response()
    response.status_code = 200
    response._content = ''
    if method == 'GET':
        
        result = '<NotificationConfiguration xmlns="%s">' % XMLNS_S3
        if bucket in S3_NOTIFICATIONS:
            notifs = S3_NOTIFICATIONS[bucket]
            for notif in notifs:
                for dest in NOTIFICATION_DESTINATION_TYPES:
                    if dest in notif:
                        dest_dict = {
                            '%sConfiguration' % dest: {
                                'Id': uuid.uuid4(),
                                dest: notif[dest],
                                'Event': notif['Event'],
                                'Filter': notif['Filter']
                            }