diff --git a/misp_stix_converter/stix2misp/stix2_to_misp.py b/misp_stix_converter/stix2misp/stix2_to_misp.py
index 22c03ab..a49d4e8 100644
--- a/misp_stix_converter/stix2misp/stix2_to_misp.py
+++ b/misp_stix_converter/stix2misp/stix2_to_misp.py
@@ -1,6 +1,7 @@
 #!/usr/bin/env python3
 # -*- coding: utf-8 -*-
 
+from __future__ import annotations
 import sys
 from .exceptions import (
     MarkingDefinitionLoadingError, ObjectRefLoadingError,