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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 headers.get(CONTENT_SHA256_HEADER) == STREAMING_HMAC_PAYLOAD:
            modified_data = strip_chunk_signatures(modified_data or data)
            headers['content-length'] = headers.get('x-amz-decoded-content-length')
        
        
        if method == 'POST':
            original_data = modified_data or data
            expanded_data = multipart_content.expand_multipart_filename(original_data, headers)
            if expanded_data is not original_data:
                modified_data = expanded_data
        
        
        if method == 'PUT' and not headers.get('content-type'):
            headers['content-type'] = 'binary/octet-stream'
        
        query = parsed_path.query
        path = parsed_path.path
        bucket = path.split('/')[1]
        query_map = urlparse.parse_qs(query, keep_blank_values=True)
        
        append_metadata_headers(method, query_map, headers)
        
        headers_changed = fix_metadata_key_underscores(request_headers=headers)
        if query == 'notification' or 'notification' in query_map:
            
            response = handle_notification_request(bucket, method, data)
            return response
        if query == 'cors' or 'cors' in query_map: