tempfile: Fix TypeVar usage (#7939)

Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>

Author: AlexWaygood

stdlib/tempfile.pyi

@@ -1,7 +1,7 @@
 import io
 import os
 import sys
-from _typeshed import Self, WriteableBuffer
+from _typeshed import Self, StrPath, WriteableBuffer
 from collections.abc import Iterable, Iterator
 from types import TracebackType
 from typing import IO, Any, AnyStr, Generic, overload
@@ -380,20 +380,22 @@ class TemporaryDirectory(Generic[AnyStr]):
     if sys.version_info >= (3, 9):
         def __class_getitem__(cls, item: Any) -> GenericAlias: ...
 
+# The overloads overlap, but they should still work fine.
 @overload
-def mkstemp() -> tuple[int, str]: ...
+def mkstemp(  # type: ignore[misc]
+    suffix: str | None = ..., prefix: str | None = ..., dir: _DirT[str] | None = ..., text: bool = ...
+) -> tuple[int, str]: ...
 @overload
 def mkstemp(
-    suffix: AnyStr | None = ..., prefix: AnyStr | None = ..., dir: _DirT[AnyStr] | None = ..., text: bool = ...
-) -> tuple[int, AnyStr]: ...
-@overload
-def mkdtemp() -> str: ...
-@overload
-def mkdtemp(suffix: AnyStr | None = ..., prefix: AnyStr | None = ..., dir: _DirT[AnyStr] | None = ...) -> AnyStr: ...
+    suffix: bytes | None = ..., prefix: bytes | None = ..., dir: _DirT[bytes] | None = ..., text: bool = ...
+) -> tuple[int, bytes]: ...
+
+# The overloads overlap, but they should still work fine.
 @overload
-def mktemp() -> str: ...
+def mkdtemp(suffix: str | None = ..., prefix: str | None = ..., dir: _DirT[str] | None = ...) -> str: ...  # type: ignore[misc]
 @overload
-def mktemp(suffix: AnyStr | None = ..., prefix: AnyStr | None = ..., dir: _DirT[AnyStr] | None = ...) -> AnyStr: ...
+def mkdtemp(suffix: bytes | None = ..., prefix: bytes | None = ..., dir: _DirT[bytes] | None = ...) -> bytes: ...
+def mktemp(suffix: str = ..., prefix: str = ..., dir: StrPath | None = ...) -> str: ...
 def gettempdirb() -> bytes: ...
 def gettempprefixb() -> bytes: ...
 def gettempdir() -> str: ...