Closes #14902: Fixed timezone conversion of a date/time in the past. Thanks to Yuriy Syrovetskiy for the report and Juancarlo Añez for the patch on which this fix is based.

Also eliminates some C code in Python/import.c as well.

Patch by Eric Snow with verification by comparing against another
patch from Jeff Knupp.

importlib.__init__, then catch the KeyError raised, not ImportError.

file size header field.

Thanks to Marc Abramowitz and Ronan Lamy for helping out with various
parts of the patch.

  Regenerate aclocalm4 and configure.

  Regenerate aclocalm4 and configure.

  from GCC for native builds

OSError.__init__ could produce incomplete instances, leading to crashes
when calling str() on them.