diff --git a/bindings/python/py_src/tokenizers/implementations/sentencepiece_unigram.py b/bindings/python/py_src/tokenizers/implementations/sentencepiece_unigram.py
index add4aada3..3d26a85e5 100644
--- a/bindings/python/py_src/tokenizers/implementations/sentencepiece_unigram.py
+++ b/bindings/python/py_src/tokenizers/implementations/sentencepiece_unigram.py
@@ -1,6 +1,6 @@
 import json
 import os
-from typing import Iterator, List, Optional, Union
+from typing import Iterator, List, Optional, Union, Tuple
 
 from tokenizers import AddedToken, Regex, Tokenizer, decoders, normalizers, pre_tokenizers, trainers
 from tokenizers.models import Unigram