bpo-39481: PEP 585 for a variety of modules (GH-19423)

- concurrent.futures
- ctypes
- http.cookies
- multiprocessing
- queue
- tempfile
- unittest.case
- urllib.parse
diff --git a/Lib/multiprocessing/managers.py b/Lib/multiprocessing/managers.py
index 1668220..9d490a1 100644
--- a/Lib/multiprocessing/managers.py
+++ b/Lib/multiprocessing/managers.py
@@ -21,6 +21,7 @@
 import array
 import queue
 import time
+import types
 import os
 from os import getpid
 
@@ -1129,6 +1130,8 @@
         return self._callmethod('set', (value,))
     value = property(get, set)
 
+    __class_getitem__ = classmethod(types.GenericAlias)
+
 
 BaseListProxy = MakeProxyType('BaseListProxy', (
     '__add__', '__contains__', '__delitem__', '__getitem__', '__len__',
diff --git a/Lib/multiprocessing/pool.py b/Lib/multiprocessing/pool.py
index 41dd923..b8a0b82 100644
--- a/Lib/multiprocessing/pool.py
+++ b/Lib/multiprocessing/pool.py
@@ -20,6 +20,7 @@
 import threading
 import time
 import traceback
+import types
 import warnings
 from queue import Empty
 
@@ -780,6 +781,8 @@
         del self._cache[self._job]
         self._pool = None
 
+    __class_getitem__ = classmethod(types.GenericAlias)
+
 AsyncResult = ApplyResult       # create alias -- see #17805
 
 #
diff --git a/Lib/multiprocessing/queues.py b/Lib/multiprocessing/queues.py
index d112db2..8350701 100644
--- a/Lib/multiprocessing/queues.py
+++ b/Lib/multiprocessing/queues.py
@@ -14,6 +14,7 @@
 import threading
 import collections
 import time
+import types
 import weakref
 import errno
 
@@ -366,3 +367,5 @@
         else:
             with self._wlock:
                 self._writer.send_bytes(obj)
+
+    __class_getitem__ = classmethod(types.GenericAlias)
diff --git a/Lib/multiprocessing/shared_memory.py b/Lib/multiprocessing/shared_memory.py
index 184e367..9f954d9 100644
--- a/Lib/multiprocessing/shared_memory.py
+++ b/Lib/multiprocessing/shared_memory.py
@@ -14,6 +14,7 @@
 import errno
 import struct
 import secrets
+import types
 
 if os.name == "nt":
     import _winapi
@@ -508,3 +509,5 @@
                 return position
         else:
             raise ValueError(f"{value!r} not in this container")
+
+    __class_getitem__ = classmethod(types.GenericAlias)