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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?
response = Response()
    response._content = """<ErrorResponse xmlns="http://sns.amazonaws.com/doc/2010-03-31/"><Error>
        <Type>Sender</Type>
        <Code>{code_string}</Code>
        <Message>{message}</Message>
        </Error><RequestId>{req_id}</RequestId>
        </ErrorResponse>""".format(message=message, code_string=code_string, req_id=short_uid())
    response.status_code = code
    return response
def create_sns_message_body(subscriber, req_data):
    message = req_data['Message'][0]
    subject = req_data.get('Subject', [None])[0]
    protocol = subscriber['Protocol']
    if six.PY2 and type(message).__name__ == 'unicode':
        
        message = message.encode('raw-unicode-escape')
    if is_raw_message_delivery(subscriber):
        return message
    if req_data.get('MessageStructure') == ['json']:
        message = json.loads(message)
        try:
            message = message.get(protocol, message['default'])
        except KeyError:
            raise Exception("Unable to find 'default' key in message payload")
    data = {
        'Type': req_data.get('Type', ['Notification'])[0],
        'MessageId': str(uuid.uuid4()),
        'Token': req_data.get('Token', [None])[0],
        'TopicArn': subscriber['TopicArn'],