TYP: Add typing for the keepdims param. of 'average' and 'ma.average'

This is a follow-up to numpygh-21485.

Author: WarrenWeckesser

numpy/lib/function_base.pyi

@@ -110,55 +110,63 @@ def average(
     axis: None = ...,
     weights: None | _ArrayLikeFloat_co= ...,
     returned: L[False] = ...,
+    keepdims: L[False] = ...,
 ) -> floating[Any]: ...
 @overload
 def average(
     a: _ArrayLikeComplex_co,
     axis: None = ...,
     weights: None | _ArrayLikeComplex_co = ...,
     returned: L[False] = ...,
+    keepdims: L[False] = ...,
 ) -> complexfloating[Any, Any]: ...
 @overload
 def average(
     a: _ArrayLikeObject_co,
     axis: None = ...,
     weights: None | Any = ...,
     returned: L[False] = ...,
+    keepdims: L[False] = ...,
 ) -> Any: ...
 @overload
 def average(
     a: _ArrayLikeFloat_co,
     axis: None = ...,
     weights: None | _ArrayLikeFloat_co= ...,
     returned: L[True] = ...,
+    keepdims: L[False] = ...,
 ) -> _2Tuple[floating[Any]]: ...
 @overload
 def average(
     a: _ArrayLikeComplex_co,
     axis: None = ...,
     weights: None | _ArrayLikeComplex_co = ...,
     returned: L[True] = ...,
+    keepdims: L[False] = ...,
 ) -> _2Tuple[complexfloating[Any, Any]]: ...
 @overload
 def average(
     a: _ArrayLikeObject_co,
     axis: None = ...,
     weights: None | Any = ...,
     returned: L[True] = ...,
+    keepdims: L[False] = ...,
 ) -> _2Tuple[Any]: ...
 @overload
 def average(
     a: _ArrayLikeComplex_co | _ArrayLikeObject_co,
     axis: None | _ShapeLike = ...,
     weights: None | Any = ...,
     returned: L[False] = ...,
+    keepdims: bool = ...,
 ) -> Any: ...
 @overload
 def average(
     a: _ArrayLikeComplex_co | _ArrayLikeObject_co,
     axis: None | _ShapeLike = ...,
     weights: None | Any = ...,
     returned: L[True] = ...,
+    keepdims: bool = ...,
 ) -> _2Tuple[Any]: ...
 
 @overload

numpy/ma/extras.pyi

@@ -44,7 +44,7 @@ diagflat: _fromnxfunction_single
 
 def apply_along_axis(func1d, axis, arr, *args, **kwargs): ...
 def apply_over_axes(func, a, axes): ...
-def average(a, axis=..., weights=..., returned=...): ...
+def average(a, axis=..., weights=..., returned=..., keepdims=...): ...
 def median(a, axis=..., out=..., overwrite_input=..., keepdims=...): ...
 def compress_nd(x, axis=...): ...
 def compress_rowcols(x, axis=...): ...