diff --git a/docs/source/serialization.rst b/docs/source/serialization.rst
index c5b597fce..7cf80aec1 100644
--- a/docs/source/serialization.rst
+++ b/docs/source/serialization.rst
@@ -11,6 +11,7 @@ Here is the serialization and deserialization flow::
   import copy
   import tempfile
   import torch
+  from torchao.utils import get_model_size_in_bytes
   from torchao.quantization.quant_api import (
       quantize_,
       int4_weight_only,