Make multiprocessing.Queue a subclass of queue.Queue

Also change multiprocessing.Queue's put and get timeout arguments to
allow None.

This fixes a problem with logging.handlers.QueueHandler and
QueueListener not accepting a multiprocessing.Queue as the queue
argument.

Declaring the Queue now needs to note what it will be used for. eg.
q = multiprocessing.Queue()    # type: multiprocessing.Queue[List[Any]]

Author: bcl

stdlib/3/multiprocessing/__init__.pyi

@@ -1,13 +1,16 @@
 # Stubs for multiprocessing
 
-from typing import Any, Callable, Iterable, Mapping, Optional, Dict, List, Union
+from typing import Any, Callable, Iterable, Mapping, Optional, Dict, List, Union, TypeVar
 
 from logging import Logger
 from multiprocessing.context import BaseContext
 from multiprocessing.managers import SyncManager
 from multiprocessing.pool import AsyncResult
 from multiprocessing.process import current_process as current_process
 import sys
+import queue
+
+_T = TypeVar('_T')
 
 class Lock():
     def acquire(self, block: bool = ..., timeout: int = ...) -> None: ...
@@ -93,15 +96,15 @@ class Process():
     def is_alive(self) -> bool: ...
     def join(self, timeout: Optional[float] = ...) -> None: ...
 
-class Queue():
+class Queue(queue.Queue[_T]):
     def __init__(self, maxsize: int = ...) -> None: ...
-    def get(self, block: bool = ..., timeout: float = ...) -> Any: ...
-    def put(self, item: Any, block: bool = ..., timeout: float = ...) -> None: ...
+    def get(self, block: bool = ..., timeout: Optional[float] = ...) -> _T: ...
+    def put(self, item: _T, block: bool = ..., timeout: Optional[float] = ...) -> None: ...
     def qsize(self) -> int: ...
     def empty(self) -> bool: ...
     def full(self) -> bool: ...
-    def put_nowait(self, item: Any) -> None: ...
-    def get_nowait(self) -> Any: ...
+    def put_nowait(self, item: _T) -> None: ...
+    def get_nowait(self) -> _T: ...
     def close(self) -> None: ...
     def join_thread(self) -> None: ...
     def cancel_join_thread(self) -> None: ...