diff --git a/mace/python/tools/converter_tool/transformer.py b/mace/python/tools/converter_tool/transformer.py
index 1fb61f715f05ea406294afc6fa53cde831869a43..657d344579c2f305a74d0120bba4e0159368aa4c 100644
--- a/mace/python/tools/converter_tool/transformer.py
+++ b/mace/python/tools/converter_tool/transformer.py
@@ -29,6 +29,7 @@ from mace.python.tools.converter_tool.base_converter import FilterFormat
 from mace.python.tools.converter_tool.base_converter import MaceKeyword
 from mace.python.tools.converter_tool.base_converter import MaceOp
 from mace.python.tools.converter_tool.base_converter import PaddingMode
+from mace.python.tools.converter_tool.base_converter import ReduceType
 from mace.python.tools.converter_tool.base_converter import TransformerRule
 from mace.python.tools.convert_util import mace_check
 from mace.python.tools.quantization import quantize_util