bpo-34353: Added sockets to stat.filemode fallback python implementation

[FortStatement]

[bpo-34353](https://www.bugs.python.org/issue34353): Add sockets to stat.filemode fallback python implementation

https://bugs.python.org/issue34353

[the-knights-who-say-ni]

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[FortStatement]

New account, only now signed the CLA 👍

[benjaminp]

Could you update Lib/test/test_stat.py to ensure this behavior is tested, too?

[benjaminp]

Looks good. Just two more nits.

[benjaminp]

It would cleaner to either do with socket.socket(socket.AF_UNIX): <rest of function> or use self.addCleanup(s.close) after the first line.

[FortStatement]

Fixed

[FortStatement]

I didn't realise you could use socket as a context manager, I'll definitely be using that in the future! Thanks!

[benjaminp]

You can add yourself to Misc/ACKS. Usually, we leave names off NEWS entries, though.

[FortStatement]

Fixed