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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?
pass
        if response:
            reset_content_length = False
            
            append_cors_headers(bucket_name, request_method=method, request_headers=headers, response=response)
            append_last_modified_headers(response=response)
            append_list_objects_marker(method, path, data, response)
            fix_location_constraint(response)
            fix_range_content_type(bucket_name, path, headers, response)
            fix_delete_objects_response(bucket_name, method, parsed, data, headers, response)
            fix_metadata_key_underscores(response=response)
            fix_creation_date(method, path, response=response)
            fix_etag_for_multipart(data, headers, response)
            
            
            if method == 'PUT' and ('X-Amz-Security-Token=' in path or
                    'X-Amz-Credential=' in path or 'AWSAccessKeyId=' in path):
                response._content = ''
                reset_content_length = True
            response_content_str = None
            try:
                response_content_str = to_str(response._content)
            except Exception:
                pass
            
            
            if method == 'GET':
                query_map = urlparse.parse_qs(parsed.query, keep_blank_values=True)
                for param_name, header_name in ALLOWED_HEADER_OVERRIDES.items():
                    if param_name in query_map: