diff --git a/pandas/core/series.py b/pandas/core/series.py
index 7f26b3d438a369..865349410fe816 100644
--- a/pandas/core/series.py
+++ b/pandas/core/series.py
@@ -5009,7 +5009,7 @@ def rename_axis(  # type: ignore[override]
         self,
         mapper: ...,
         *,
-        index = ...,
+        index=...,
         axis: Axis = ...,
         copy: bool = ...,
         inplace: bool = Literal[True],
@@ -5021,7 +5021,7 @@ def rename_axis(  # type: ignore[override]
         self,
         mapper: ...,
         *,
-        index = ...,
+        index=...,
         axis: Axis = ...,
         copy: bool = ...,
         inplace: bool = Literal[False],
@@ -5033,7 +5033,7 @@ def rename_axis(  # type: ignore[override]
         self,
         mapper: ...,
         *,
-        index = ...,
+        index=...,
         axis: Axis = ...,
         copy: bool = ...,
         inplace: bool = ...,