diff --git a/pandas/util/_decorators.py b/pandas/util/_decorators.py
index 39a729bc51f35..2b160d2946b2b 100644
--- a/pandas/util/_decorators.py
+++ b/pandas/util/_decorators.py
@@ -435,7 +435,7 @@ def some_function(x):
         "%s %s wrote the Raven"
     """
 
-    def __init__(self, *args, **kwargs):
+    def __init__(self, *args, **kwargs) -> None:
         if args and kwargs:
             raise AssertionError("Only positional or keyword args are allowed")
 
@@ -475,7 +475,7 @@ def my_dog(has='fleas'):
 
     addendum: str | None
 
-    def __init__(self, addendum: str | None, join: str = "", indents: int = 0):
+    def __init__(self, addendum: str | None, join: str = "", indents: int = 0) -> None:
         if indents > 0:
             self.addendum = indent(addendum, indents=indents)
         else:
diff --git a/pandas/util/_doctools.py b/pandas/util/_doctools.py
index 0d90d9b2871d9..18fb9a7e055b5 100644
--- a/pandas/util/_doctools.py
+++ b/pandas/util/_doctools.py
@@ -16,7 +16,7 @@ def __init__(
         cell_width: float = 0.37,
         cell_height: float = 0.25,
         font_size: float = 7.5,
-    ):
+    ) -> None:
         self.cell_width = cell_width
         self.cell_height = cell_height
         self.font_size = font_size