diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index f821d4b..b67bd20 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -13,7 +13,7 @@ ci:
 
 repos:
   - repo: https://github.com/compilerla/conventional-pre-commit
-    rev: v3.1.0
+    rev: v3.2.0
     hooks:
       - id: conventional-pre-commit
         stages: [commit-msg]
@@ -36,7 +36,7 @@ repos:
           ]
 
   - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v4.5.0
+    rev: v4.6.0
     hooks:
       - id: trailing-whitespace
       - id: end-of-file-fixer
@@ -70,7 +70,7 @@ repos:
       - id: text-unicode-replacement-char
 
   - repo: https://github.com/Lucas-C/pre-commit-hooks-safety
-    rev: v1.3.2
+    rev: v1.3.3
     hooks:
       - id: python-safety-dependencies-check
         files: pyproject.toml
@@ -81,7 +81,7 @@ repos:
       - id: docformatter
 
   - repo: https://github.com/nbQA-dev/nbQA
-    rev: 1.7.1
+    rev: 1.8.5
     hooks:
       - id: nbqa-check-ast
       - id: nbqa-mypy
@@ -89,17 +89,17 @@ repos:
       - id: nbqa-pyupgrade
 
   - repo: https://github.com/bwhmather/ssort
-    rev: 0.12.2
+    rev: 0.12.4
     hooks:
       - id: ssort
 
   - repo: https://github.com/asottile/pyupgrade
-    rev: v3.15.0
+    rev: v3.15.2
     hooks:
       - id: pyupgrade
 
   - repo: https://github.com/psf/black
-    rev: 23.12.1
+    rev: 24.4.0
     hooks:
       - id: black
       - id: black-jupyter
@@ -112,13 +112,13 @@ repos:
         args: ["--profile=black"]
 
   - repo: https://github.com/PyCQA/pylint
-    rev: v3.0.3
+    rev: v3.1.0
     hooks:
       - id: pylint
         args: ["--rcfile=pyproject.toml"]
 
   - repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v1.8.0
+    rev: v1.9.0
     hooks:
       - id: mypy
         args:
@@ -126,7 +126,7 @@ repos:
         exclude: "tests"
 
   - repo: https://github.com/PyCQA/bandit
-    rev: 1.7.6
+    rev: 1.7.8
     hooks:
       - id: bandit
         exclude: "^tests/"
@@ -134,12 +134,12 @@ repos:
           - "-r"
 
   - repo: https://github.com/kynan/nbstripout
-    rev: 0.6.1
+    rev: 0.7.1
     hooks:
       - id: nbstripout
 
   - repo: https://github.com/python-poetry/poetry
-    rev: 1.7.0
+    rev: 1.8.0
     hooks:
       - id: poetry-check
       - id: poetry-lock
diff --git a/src/sk_transformers/generic_transformer.py b/src/sk_transformers/generic_transformer.py
index c145d45..e882950 100644
--- a/src/sk_transformers/generic_transformer.py
+++ b/src/sk_transformers/generic_transformer.py
@@ -291,9 +291,11 @@ def transform(self, X: pd.DataFrame) -> pd.DataFrame:
 
             agg_df = X.groupby(groupby_columns).agg(
                 [
-                    getattr(pl, agg_func)(agg_column).alias(agg_new_column)
-                    if isinstance(agg_func, str)
-                    else pl.col(agg_column).apply(agg_func).alias(agg_new_column)
+                    (
+                        getattr(pl, agg_func)(agg_column).alias(agg_new_column)
+                        if isinstance(agg_func, str)
+                        else pl.col(agg_column).apply(agg_func).alias(agg_new_column)
+                    )
                     for (agg_column, agg_func, agg_new_column) in agg_features
                 ]
             )
diff --git a/src/sk_transformers/string_transformer.py b/src/sk_transformers/string_transformer.py
index d7bb218..22e064e 100644
--- a/src/sk_transformers/string_transformer.py
+++ b/src/sk_transformers/string_transformer.py
@@ -489,9 +489,11 @@ def __init__(
     ) -> None:
         super().__init__()
         self.features = [
-            (split_tuple[0], split_tuple[1], split_tuple[2])
-            if len(split_tuple) == 3
-            else (split_tuple[0], split_tuple[1], -1)
+            (
+                (split_tuple[0], split_tuple[1], split_tuple[2])
+                if len(split_tuple) == 3
+                else (split_tuple[0], split_tuple[1], -1)
+            )
             for split_tuple in features
         ]
 
@@ -515,20 +517,22 @@ def transform(self, X: pd.DataFrame) -> pd.DataFrame:
         ]
 
         select_with_expr = [
-            pl.col(column)
-            .str.splitn(by=separator, n=max_possible_split + 1)
-            .struct.rename_fields(
-                [column + f"_part_{i}" for i in range(1, max_possible_split + 2)]
-            )
-            .alias(column + "_alias")
-            if maxsplit in [0, -1] or maxsplit > max_possible_split
-            else (
+            (
                 pl.col(column)
-                .str.splitn(by=separator, n=maxsplit + 1)
+                .str.splitn(by=separator, n=max_possible_split + 1)
                 .struct.rename_fields(
-                    [column + f"_part_{i}" for i in range(1, maxsplit + 2)]
+                    [column + f"_part_{i}" for i in range(1, max_possible_split + 2)]
                 )
                 .alias(column + "_alias")
+                if maxsplit in [0, -1] or maxsplit > max_possible_split
+                else (
+                    pl.col(column)
+                    .str.splitn(by=separator, n=maxsplit + 1)
+                    .struct.rename_fields(
+                        [column + f"_part_{i}" for i in range(1, maxsplit + 2)]
+                    )
+                    .alias(column + "_alias")
+                )
             )
             for (column, separator, maxsplit), max_possible_split in zip(
                 self.features, max_possible_splits_list