diff --git a/quinn/math.py b/quinn/math.py
index 203d27f9..0302f9ad 100644
--- a/quinn/math.py
+++ b/quinn/math.py
@@ -1,4 +1,6 @@
 """Math routines for PySpark."""
+from __future__ import annotations
+
 from typing import Optional, Union
 
 from pyspark.sql import Column