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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?
if req_action == 'CreateTopic' and response.status_code < 400:
                response_data = xmltodict.parse(response.content)
                topic_arn = response_data['CreateTopicResponse']['CreateTopicResult']['TopicArn']
                do_create_topic(topic_arn)
                
                event_publisher.fire_event(
                    event_publisher.EVENT_SNS_CREATE_TOPIC,
                    payload={'t': event_publisher.get_hash(topic_arn)}
                )
            if req_action == 'DeleteTopic' and response.status_code < 400:
                
                topic_arn = (req_data.get('TargetArn') or req_data.get('TopicArn'))[0]
                event_publisher.fire_event(
                    event_publisher.EVENT_SNS_DELETE_TOPIC,
                    payload={'t': event_publisher.get_hash(topic_arn)}
                )
UPDATE_SNS = ProxyListenerSNS()
def publish_message(topic_arn, req_data, subscription_arn=None):
    message = req_data['Message'][0]
    sqs_client = aws_stack.connect_to_service('sqs')
    for subscriber in SNS_SUBSCRIPTIONS.get(topic_arn, []):
        if subscription_arn not in [None, subscriber['SubscriptionArn']]:
            continue
        filter_policy = json.loads(subscriber.get('FilterPolicy') or '{}')
        message_attributes = get_message_attributes(req_data)
        if not check_filter_policy(filter_policy, message_attributes):
            continue
        if subscriber['Protocol'] == 'sqs':
            try:
                endpoint = subscriber['Endpoint']