Antoine Pitrou  committed 565734c

Remove outdated statements about threading and imports.

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  • Parent commits 364289c

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File Doc/library/multiprocessing.rst

           print(q.get())    # prints "[42, None, 'hello']"
-   Queues are thread and process safe, but note that they must never
-   be instantiated as a side effect of importing a module: this can lead
-   to a deadlock!  (see :ref:`threaded-imports`)
+   Queues are thread and process safe.

File Doc/library/threading.rst

 Currently, :class:`Lock`, :class:`RLock`, :class:`Condition`,
 :class:`Semaphore`, and :class:`BoundedSemaphore` objects may be used as
 :keyword:`with` statement context managers.
-.. _threaded-imports:
-Importing in threaded code
-While the import machinery is thread-safe, there are two key restrictions on
-threaded imports due to inherent limitations in the way that thread-safety is
-* Firstly, other than in the main module, an import should not have the
-  side effect of spawning a new thread and then waiting for that thread in
-  any way. Failing to abide by this restriction can lead to a deadlock if
-  the spawned thread directly or indirectly attempts to import a module.
-* Secondly, all import attempts must be completed before the interpreter
-  starts shutting itself down. This can be most easily achieved by only
-  performing imports from non-daemon threads created through the threading
-  module. Daemon threads and threads created directly with the thread
-  module will require some other form of synchronization to ensure they do
-  not attempt imports after system shutdown has commenced. Failure to
-  abide by this restriction will lead to intermittent exceptions and
-  crashes during interpreter shutdown (as the late imports attempt to
-  access machinery which is no longer in a valid state).