CLN: no return on init

Author: Maximilian Roos <[email protected]>

Closes #13197 from MaximilianR/init-return and squashes the following commits:

ee5072a [Maximilian Roos] formatting

Author: max-sixty

pandas/core/window.py

@@ -985,10 +985,8 @@ class Expanding(_Rolling_and_Expanding):
 
     def __init__(self, obj, min_periods=1, freq=None, center=False, axis=0,
                  **kwargs):
-        return super(Expanding, self).__init__(obj=obj,
-                                               min_periods=min_periods,
-                                               freq=freq, center=center,
-                                               axis=axis)
+        super(Expanding, self).__init__(obj=obj, min_periods=min_periods,
+                                        freq=freq, center=center, axis=axis)
 
     @property
     def _constructor(self):