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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 topic_arn not in SNS_SUBSCRIPTIONS:
        SNS_SUBSCRIPTIONS[topic_arn] = []
def do_delete_topic(topic_arn):
    SNS_SUBSCRIPTIONS.pop(topic_arn, None)
def do_confirm_subscription(topic_arn, token):
    for k, v in SUBSCRIPTION_STATUS.items():
        if v['Token'] == token and v['TopicArn'] == topic_arn:
            v['Status'] = 'Subscribed'
def do_subscribe(topic_arn, endpoint, protocol, subscription_arn, attributes, filter_policy=None):
    
    
    for existing_topic_subscription in SNS_SUBSCRIPTIONS.get(topic_arn, []):
        if existing_topic_subscription.get('Endpoint') == endpoint:
            return
    subscription = {