diff --git a/examples/03-0_data_changed_signal.py b/examples/03-0_data_changed_signal.py
index 8c3e654a..b426b105 100644
--- a/examples/03-0_data_changed_signal.py
+++ b/examples/03-0_data_changed_signal.py
@@ -1,10 +1,7 @@
-import sys
 from tabulous import TableViewer
 from tabulous.types import ItemInfo
 import numpy as np
 
-PY_38 = sys.version_info <= (3, 8)
-
 if __name__ == "__main__":
     viewer = TableViewer()
     size = 100
@@ -24,15 +21,13 @@ def _on_data_change(info: ItemInfo):
             f"{info.old_value} to {info.value}."
         )
 
-    if PY_38:
-        # NOTE: Python <= 3.8 does not support __getitem__ in a decorator
-        def _on_data_change(info: ItemInfo):
-            print("data at row 0 changed.")
-        table.events.data[0, :].connect(_on_data_change)
+    def _on_data_change(info: ItemInfo):
+        print("data at row 0 changed.")
+    table.events.data[0, :].connect(_on_data_change)
 
-    else:
-        @table.events.data[0, :].connect
-        def _on_data_change(info: ItemInfo):
-            print("data at row 0 changed.")
+    # NOTE: Python >= 3.9 supports this syntax
+    # >>> @table.events.data[0, :].connect
+    # >>> def _on_data_change(info: ItemInfo):
+    # ...     print("data at row 0 changed.")
 
     viewer.show()
diff --git a/tabulous/_colormap.py b/tabulous/_colormap.py
index e82de8fc..e3a7d645 100644
--- a/tabulous/_colormap.py
+++ b/tabulous/_colormap.py
@@ -10,9 +10,8 @@
     import pandas as pd
 
     _TimeLike = Union[pd.Timestamp, pd.Timedelta]
+    _ColorType = tuple[int, int, int, int]
 
-
-_ColorType = tuple[int, int, int, int]
 _DEFAULT_MIN = "#697FD1"
 _DEFAULT_MAX = "#FF696B"
 
diff --git a/tabulous/commands/_dialogs.py b/tabulous/commands/_dialogs.py
index 9c2ef338..faf54c9a 100644
--- a/tabulous/commands/_dialogs.py
+++ b/tabulous/commands/_dialogs.py
@@ -1,5 +1,5 @@
 from functools import partial
-from typing import List, Union, TYPE_CHECKING
+from typing import List, Union, TYPE_CHECKING, Tuple
 from typing_extensions import Annotated
 
 import logging
@@ -206,7 +206,7 @@ def hist(
     label: SelectionOperator,
     table: TableBase,
     bins: int = 10,
-    range: tuple[str, str] = ("", ""),
+    range: Tuple[str, str] = ("", ""),
     alpha: float = 1.0,
     density: bool = False,
     histtype: str = "bar",
diff --git a/tabulous/widgets/_table.py b/tabulous/widgets/_table.py
index fdfdfd6d..dd036777 100644
--- a/tabulous/widgets/_table.py
+++ b/tabulous/widgets/_table.py
@@ -596,7 +596,10 @@ def _normalize_data(data) -> pd.DataFrame:
         import pandas as pd
 
         if not isinstance(data, pd.DataFrame):
-            mod = type(data).__module__.split(".", 1)[0]
+            try:
+                mod = type(data).__module__.split(".", 1)[0]
+            except AttributeError:
+                mod = ""
             if mod == "polars":
                 import polars as pl
 
diff --git a/tests/test_core.py b/tests/test_core.py
index 64409de9..73b712c0 100644
--- a/tests/test_core.py
+++ b/tests/test_core.py
@@ -17,7 +17,7 @@ def test_io():
     tbl.read_csv(DATA_PATH / "test.csv").close()
 
 @pytest.mark.parametrize(
-    "fname", [f for f in glob("examples/*.py") if "napari" not in f]
+    "fname", [f for f in glob("examples/*.py") if "napari" not in f and "seaborn" not in f]
 )
 def test_examples(fname):
     with warnings.catch_warnings():