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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?
'TopicArn': topic_arn,
        'Endpoint': endpoint,
        'Protocol': protocol,
        'SubscriptionArn': subscription_arn,
        'FilterPolicy': filter_policy
    }
    subscription.update(attributes)
    SNS_SUBSCRIPTIONS[topic_arn].append(subscription)
    if subscription_arn not in SUBSCRIPTION_STATUS.keys():
        SUBSCRIPTION_STATUS[subscription_arn] = {}
    SUBSCRIPTION_STATUS[subscription_arn].update(
        {
            'TopicArn': topic_arn,
            'Token': short_uid(),
            'Status': 'Not Subscribed'
        }
    )
    
    if protocol in ['http', 'https']:
        token = short_uid()
        external_url = external_service_url('sns')
        confirmation = {
            'Type': ['SubscriptionConfirmation'],
            'Token': [token],
            'Message': [('You have chosen to subscribe to the topic %s.\n' % topic_arn) +
                        'To confirm the subscription, visit the SubscribeURL included in this message.'],
            'SubscribeURL': ['%s/?Action=ConfirmSubscription&TopicArn=%s&Token=%s' % (external_url, topic_arn, token)]
        }
        publish_message(topic_arn, confirmation, subscription_arn)
def do_unsubscribe(subscription_arn):