diff --git a/library/train_util.py b/library/train_util.py
index 43a8a0fe..ba6e4cb9 100644
--- a/library/train_util.py
+++ b/library/train_util.py
@@ -434,7 +434,7 @@ class BaseSubset:
         custom_attributes: Optional[Dict[str, Any]] = None,
         validation_seed: Optional[int] = None,
         validation_split: Optional[float] = 0.0,
-        system_prompt: Optional[str] = None
+        system_prompt: Optional[str] = None,
         resize_interpolation: Optional[str] = None,
     ) -> None:
         self.image_dir = image_dir
@@ -500,7 +500,7 @@ class DreamBoothSubset(BaseSubset):
         custom_attributes: Optional[Dict[str, Any]] = None,
         validation_seed: Optional[int] = None,
         validation_split: Optional[float] = 0.0,
-        system_prompt: Optional[str] = None
+        system_prompt: Optional[str] = None,
         resize_interpolation: Optional[str] = None,
     ) -> None:
         assert image_dir is not None, "image_dir must be specified / image_dirは指定が必須です"
@@ -529,7 +529,7 @@ class DreamBoothSubset(BaseSubset):
             custom_attributes=custom_attributes,
             validation_seed=validation_seed,
             validation_split=validation_split,
-            system_prompt=system_prompt
+            system_prompt=system_prompt,
             resize_interpolation=resize_interpolation,
         )
 
@@ -573,7 +573,7 @@ class FineTuningSubset(BaseSubset):
         custom_attributes: Optional[Dict[str, Any]] = None,
         validation_seed: Optional[int] = None,
         validation_split: Optional[float] = 0.0,
-        system_prompt: Optional[str] = None
+        system_prompt: Optional[str] = None,
         resize_interpolation: Optional[str] = None,
     ) -> None:
         assert metadata_file is not None, "metadata_file must be specified / metadata_fileは指定が必須です"
@@ -602,7 +602,7 @@ class FineTuningSubset(BaseSubset):
             custom_attributes=custom_attributes,
             validation_seed=validation_seed,
             validation_split=validation_split,
-            system_prompt=system_prompt
+            system_prompt=system_prompt,
             resize_interpolation=resize_interpolation,
         )
 
@@ -642,7 +642,7 @@ class ControlNetSubset(BaseSubset):
         custom_attributes: Optional[Dict[str, Any]] = None,
         validation_seed: Optional[int] = None,
         validation_split: Optional[float] = 0.0,
-        system_prompt: Optional[str] = None
+        system_prompt: Optional[str] = None,
         resize_interpolation: Optional[str] = None,
     ) -> None:
         assert image_dir is not None, "image_dir must be specified / image_dirは指定が必須です"
@@ -671,7 +671,7 @@ class ControlNetSubset(BaseSubset):
             custom_attributes=custom_attributes,
             validation_seed=validation_seed,
             validation_split=validation_split,
-            system_prompt=system_prompt
+            system_prompt=system_prompt,
             resize_interpolation=resize_interpolation,
         )