🩹 refactor type hint imports in numpy.random._pickle.pyi

Author: guan404ming

src/numpy-stubs/random/_pickle.pyi

@@ -1,5 +1,5 @@
 from collections.abc import Callable
-from typing import Literal, TypeVar, TypedDict, overload, type_check_only
+from typing import Final, Literal, TypeVar, TypedDict, overload, type_check_only
 
 from numpy.random._generator import Generator
 from numpy.random._mt19937 import MT19937
@@ -12,13 +12,15 @@ from numpy.random.mtrand import RandomState
 _T = TypeVar("_T", bound=BitGenerator)
 
 @type_check_only
-class BitGenerators(TypedDict):
+class _BitGenerators(TypedDict):
     MT19937: type[MT19937]
     PCG64: type[PCG64]
     PCG64DXSM: type[PCG64DXSM]
     Philox: type[Philox]
     SFC64: type[SFC64]
 
+BitGenerators: Final[_BitGenerators] = ...
+
 @overload
 def __bit_generator_ctor(bit_generator: Literal["MT19937"] = "MT19937") -> MT19937: ...
 @overload
@@ -32,10 +34,10 @@ def __bit_generator_ctor(bit_generator: Literal["SFC64"]) -> SFC64: ...
 @overload
 def __bit_generator_ctor(bit_generator: type[_T]) -> _T: ...
 def __generator_ctor(
-    bit_generator_name: str | type[BitGenerator] = "MT19937",
+    bit_generator_name: str | type[BitGenerator] | BitGenerator = "MT19937",
     bit_generator_ctor: Callable[[str | type[BitGenerator]], BitGenerator] = ...,
 ) -> Generator: ...
 def __randomstate_ctor(
-    bit_generator_name: str | type[BitGenerator] = "MT19937",
+    bit_generator_name: str | type[BitGenerator] | BitGenerator = "MT19937",
     bit_generator_ctor: Callable[[str | type[BitGenerator]], BitGenerator] = ...,
 ) -> RandomState: ...