diff --git a/deepmd/pt/entrypoints/main.py b/deepmd/pt/entrypoints/main.py
index d9b08319b4..27636ddd63 100644
--- a/deepmd/pt/entrypoints/main.py
+++ b/deepmd/pt/entrypoints/main.py
@@ -326,7 +326,9 @@ def main(args: Optional[Union[List[str], argparse.Namespace]] = None):
         model_params = state_dict["_extra_state"]["model_params"]
         finetune_from_multi_task = "model_dict" in model_params
         #  Pretrained model must be multitask mode
-        assert finetune_from_multi_task, "Error: The '--list-model-branch' option requires \
+        assert (
+            finetune_from_multi_task
+        ), "Error: The '--list-model-branch' option requires \
             a multitask pretrained model. The provided model does not meet this criterion"
         model_branch = list(model_params["model_dict"].keys())
         log.info(f"Available model branches are {model_branch}")