ENH: Improve Pandas scalars

pandas-stubs/core/arrays/interval.pyi

@@ -17,13 +17,17 @@ class IntervalArray(IntervalMixin, ExtensionArray):
         cls, data, closed=..., dtype=..., copy: bool = ..., verify_integrity: bool = ...
     ): ...
     @classmethod
-    def from_breaks(cls, breaks, closed: str = ..., copy: bool = ..., dtype=...): ...
+    def from_breaks(
+        cls, breaks, closed: str = ..., copy: bool = ..., dtype=...
+    ) -> IntervalArray: ...
     @classmethod
     def from_arrays(
         cls, left, right, closed: str = ..., copy: bool = ..., dtype=...
-    ): ...
+    ) -> IntervalArray: ...
     @classmethod
-    def from_tuples(cls, data, closed: str = ..., copy: bool = ..., dtype=...): ...
+    def from_tuples(
+        cls, data, closed: str = ..., copy: bool = ..., dtype=...
+    ) -> IntervalArray: ...
     def __iter__(self): ...
     def __len__(self) -> int: ...
     def __getitem__(self, value): ...

pandas-stubs/core/arrays/sparse/array.pyi

@@ -5,6 +5,8 @@ from pandas.core.arrays import (
 )
 from pandas.core.base import PandasObject
 
+from pandas._libs.sparse import SparseIndex
+
 class SparseArray(PandasObject, ExtensionArray, ExtensionOpsMixin):
     def __init__(
         self,
@@ -20,9 +22,9 @@ class SparseArray(PandasObject, ExtensionArray, ExtensionOpsMixin):
     def __array__(self, dtype=..., copy=...) -> np.ndarray: ...
     def __setitem__(self, key, value) -> None: ...
     @property
-    def sp_index(self): ...
+    def sp_index(self) -> SparseIndex: ...
     @property
-    def sp_values(self): ...
+    def sp_values(self) -> np.ndarray: ...
     @property
     def dtype(self): ...
     @property

pandas-stubs/core/construction.pyi

@@ -19,7 +19,7 @@ from pandas.core.dtypes.generic import ABCExtensionArray
 
 def array(
     # str is forbidden even though Sequence[object] allows "abc"
-    data: npt.NDArray | Sequence[object],
+    data: npt.NDArray | Sequence[object] | pd.Index | pd.Series,
     dtype: str
     | np.dtype[np.generic]
     | ExtensionDtype