The RFC doesn't say that they are allowed; apparently many mailers accept
them, but not postfix.  Contributions to this patch were made by Felipe Cruz
and Catalin Iacob.

The changeset also adds additional indirect tests for quoteaddr (null address
and IDNA-encoded address).

merge from 3.2 - Fix closes issue12577 - clarify shutil.move documentation. Patch suggestion by Catalin Iacob

Closes #12579. Positional fields with str.format_map() now raise a ValueError instead of SystemError.

restricting itself to just functions and methods (which allows
built-in functions to be used, etc.).

Closes issue #10271. Thanks to lekma for the bug report.

merge from 3.2 - Fix closes Issue12478 - HTTPErrorProcess 's methods are http_response and https_response.

merge from 3.2 - Fix closes Issue12479 - Add HTTPErrorProcessor class definition - Patch by Sandro Tosi

Fix Issue10403 - datetime documentation clarification based on review in the reitveld by Alexendar belopolsky.

shutdown() is called, without waiting for the garbage collector to kick in.

by joining all queues and processes when shutdown() is called.