diff --git a/icefall/utils.py b/icefall/utils.py
index 8bcf075e6..022f83b3b 100644
--- a/icefall/utils.py
+++ b/icefall/utils.py
@@ -47,8 +47,6 @@ from packaging import version
 from pypinyin import lazy_pinyin, pinyin
 from pypinyin.contrib.tone_convert import to_finals, to_finals_tone, to_initials
 from torch.utils.tensorboard import SummaryWriter
-from contextlib import contextmanager
-
 
 from icefall.checkpoint import average_checkpoints