diff --git a/tools/convert_diffusers20_original_sd.py b/tools/convert_diffusers20_original_sd.py
index c12478ff..7c7cc1c5 100644
--- a/tools/convert_diffusers20_original_sd.py
+++ b/tools/convert_diffusers20_original_sd.py
@@ -84,6 +84,7 @@ def setup_parser() -> argparse.ArgumentParser:
                       help="model to load: checkpoint file or Diffusers model's directory / 読み込むモデル、checkpointかDiffusers形式モデルのディレクトリ")
   parser.add_argument("model_to_save", type=str, default=None,
                       help="model to save: checkpoint (with extension) or Diffusers model's directory (without extension) / 変換後のモデル、拡張子がある場合はcheckpoint、ない場合はDiffusesモデルとして保存")
+  return parser
 
 
 if __name__ == '__main__':