selectors: Make sure EpollSelecrtor.select() works when no FD is registered.

Closes issue #23009.

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branch : 3.4
selectors: Fix typo in comment.

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branch : 3.4
NEWS: Add news entry for issue #23009.

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branch : 3.4
NEWS: Remove duplicate entry

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branch : 3.4
inspect: Fix getsource() to load updated source of reloaded module

Issue #1218234. Initial patch by Berker Peksag.

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branch : 3.4