Add multiprocessing.resource_sharer submodule (#8413)

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>

stdlib/multiprocessing/resource_sharer.pyi

@@ -0,0 +1,25 @@
+import sys
+from socket import socket
+from typing import Union
+from typing_extensions import TypeAlias
+
+__all__ = ["stop"]
+
+# https://docs.python.org/3/library/multiprocessing.html#address-formats
+_Address: TypeAlias = Union[str, tuple[str, int]]
+
+if sys.platform == "win32":
+    __all__ += ["DupSocket"]
+
+    class DupSocket:
+        def __init__(self, sock: socket) -> None: ...
+        def detach(self) -> socket: ...
+
+else:
+    __all__ += ["DupFd"]
+
+    class DupFd:
+        def __init__(self, fd: int) -> None: ...
+        def detach(self) -> int: ...
+
+def stop(timeout: float | None = ...) -> None: ...