Initial LsPower implementation

.venv/Lib/site-packages/numpy/lib/_arrayterator_impl.pyi

@@ -0,0 +1,45 @@
+# pyright: reportIncompatibleMethodOverride=false
+
+from collections.abc import Generator
+from types import EllipsisType
+from typing import Any, Final, TypeAlias, overload
+from typing_extensions import TypeVar
+
+import numpy as np
+from numpy._typing import _AnyShape, _Shape
+
+__all__ = ["Arrayterator"]
+
+_ShapeT_co = TypeVar("_ShapeT_co", bound=_Shape, default=_AnyShape, covariant=True)
+_DTypeT = TypeVar("_DTypeT", bound=np.dtype)
+_DTypeT_co = TypeVar("_DTypeT_co", bound=np.dtype, default=np.dtype, covariant=True)
+_ScalarT = TypeVar("_ScalarT", bound=np.generic)
+
+_AnyIndex: TypeAlias = EllipsisType | int | slice | tuple[EllipsisType | int | slice, ...]
+
+# NOTE: In reality `Arrayterator` does not actually inherit from `ndarray`,
+# but its ``__getattr__` method does wrap around the former and thus has
+# access to all its methods
+
+class Arrayterator(np.ndarray[_ShapeT_co, _DTypeT_co]):
+    var: np.ndarray[_ShapeT_co, _DTypeT_co]  # type: ignore[assignment]
+    buf_size: Final[int | None]
+    start: Final[list[int]]
+    stop: Final[list[int]]
+    step: Final[list[int]]
+
+    @property  # type: ignore[misc]
+    def shape(self) -> _ShapeT_co: ...
+    @property
+    def flat(self: Arrayterator[Any, np.dtype[_ScalarT]]) -> Generator[_ScalarT]: ...  # type: ignore[override]
+
+    #
+    def __init__(self, /, var: np.ndarray[_ShapeT_co, _DTypeT_co], buf_size: int | None = None) -> None: ...
+    def __getitem__(self, index: _AnyIndex, /) -> Arrayterator[_AnyShape, _DTypeT_co]: ...  # type: ignore[override]
+    def __iter__(self) -> Generator[np.ndarray[_AnyShape, _DTypeT_co]]: ...
+
+    #
+    @overload  # type: ignore[override]
+    def __array__(self, /, dtype: None = None, copy: bool | None = None) -> np.ndarray[_ShapeT_co, _DTypeT_co]: ...
+    @overload
+    def __array__(self, /, dtype: _DTypeT, copy: bool | None = None) -> np.ndarray[_ShapeT_co, _DTypeT]: ...