diff --git a/egs/librispeech/ASR/transducer_stateless/conformer.py b/egs/librispeech/ASR/transducer_stateless/conformer.py
index 3386ed9b2..83e0f8bca 100644
--- a/egs/librispeech/ASR/transducer_stateless/conformer.py
+++ b/egs/librispeech/ASR/transducer_stateless/conformer.py
@@ -19,7 +19,7 @@ import copy
 import math
 import warnings
 from typing import Optional, Tuple, Sequence
-from subsampling import PeLU, ExpScale
+from subsampling import PeLU, ExpScale, ExpScaleSwish
 
 import torch
 from torch import Tensor, nn