executables used to find the mac address, with /sbin and /usr/sbin as
fallbacks.

Issue #11508: Fixed uuid.getnode() and uuid.uuid1() on environment with
virtual interface.  Original patch by Kent Frazier.

Issue #18784: The uuid module no more attempts to load libc via ctypes.CDLL,
if all necessary functions are already found in libuuid.
Patch by Evgeny Sologubov.

Issue #16102: Make uuid._netbios_getnode() work again on Python 3.