Windows.

Originally only b'PYTHONCASEOK' was being checked for in os.environ,
but that won't work under Windows where all environment variables are
strings (on OS X they are bytes).

Thanks to Eryk Sun for the bug report.

type issues be about 'path' instead of 'name'.

Thanks to Lev Maximov for the patch.

__fspath__() raises an exception.

Thanks to Xiang Zhang for the patch.

Patch by Stéphane Wirtel.

This removes one problem inport and reduces len(sys.modules) by 37.

Patch by Ammar Askar.

Patch by Evelyn Mitchell.

Patch by John Hagen.

Patch by Jim Fulton.

in case of embedded null characters/bytes.  Patch by Xiang Zhang.

in case of embedded null characters/bytes.  Patch by Xiang Zhang.