diff --git a/egs/librispeech/ASR/prepare_gigaspeech.py b/egs/librispeech/ASR/prepare_gigaspeech.py
index 831ebea50..870909787 100755
--- a/egs/librispeech/ASR/prepare_gigaspeech.py
+++ b/egs/librispeech/ASR/prepare_gigaspeech.py
@@ -9,6 +9,7 @@ import subprocess
 import sys
 from contextlib import contextmanager
 from pathlib import Path
+from functools import partial
 
 import torch