diff --git a/ffn/training/examples.py b/ffn/training/examples.py
index 13e6c2a..a6eff48 100644
--- a/ffn/training/examples.py
+++ b/ffn/training/examples.py
@@ -14,6 +14,8 @@
 # ==============================================================================
 """Utilities for building training examples for FFN training."""
 
+from __future__ import annotations
+
 import collections
 from concurrent import futures
 import itertools