diff --git a/model_utils/model.py b/model_utils/model.py
index 2ef135d2a..88ef28b92 100644
--- a/model_utils/model.py
+++ b/model_utils/model.py
@@ -18,6 +18,7 @@ import sys
 import os
 import time
 import numpy as np
+from collections import defaultdict
 
 import paddle
 from paddle import distributed as dist