ignoring altsep if it already exists on a path when doing a join.

which is different than what imp.cache_from_source() operates on.

variable name.

paths.

Thanks to Eric Snow for taking an initial stab at the implementation.

the UNC path. Also clean up sys.path and invalidate finder caches.

Thanks to Vinay Sajip for spotting the use of the wrong path.

separators.

for performance. While get_magic() could move to Lib/imp.py, having to
support PyImport_GetMagicNumber() would lead to equal, if not more, C
code than sticking with the status quo.

Issue #14339: Improve speed of bin, oct and hex builtins.  Patch by Serhiy Storchaka (with minor modifications).

as found in sys.modules and not as what the loader returns (even
though it is required to by PEP 302).

importlib.test.import_ using builtins.__import__() instead of just the
relative import tests.

extension modules.

in Python/dynload_shlibs.c.

This should fix the remaining importlib test failure on Windows.
Support in AIX and HP-UX will be in a separate checkin.

this is more readable.