Issue #20245: The open functions in the tarfile module now correctly handle empty mode.
Backported test for issue #20238.
Issue #20243: TarFile no longer raise ReadError when opened in write mode.
Issue #20270: urllib and urlparse now support empty ports.
#19855: restore use of LC_ALL, not LC_MESSAGES

I didn't realize LC_ALL was an override, and I should have.  I tried to
make a test, but it is not clear that the LC variables actually affect
the strings that uuid is using to parse the command output.
add Nikolaus Rath to ACKS