field.  Rather than cluttering the tests, translate the arguably more correct
"None" to an empty string.

Patch by Xiang Zhang.

Patch by Xiang Zhang.

If they aren't present, set them to an empty string.

Issue #26804: urllib.request will prefer lower_case proxy environment variables
over UPPER_CASE or Mixed_Case ones.

Patch contributed by Hans-Peter Jansen. Reviewed by Martin Panter and Senthil Kumaran.

over UPPER_CASE or Mixed_Case ones.

Patch contributed by Hans-Peter Jansen. Reviewed by Martin Panter and Senthil Kumaran.

Reported by Saul Spatz on docs@

Minimal supported Tcl/Tk version is 8.4, and this is checked in _tkinter.c.

differing items (like bytes in the -b mode).  This affects assertListEqual()
and assertTupleEqual().

There were duplicated methods with the same name and body.

It is not needed since tests use unittest.main().

Optimizations section.

reopened on Windows.  Added tests for fallbacks.

reopened on Windows.  Added tests for fallbacks.

Patch by Jon Dufresne.