Not all code has been fixed yet; this is just a checkpoint...
The C API still has PyDict_HasKey() and _HasKeyString(); not sure
if I want to change those just yet.

after a failed import.

This is the last checkin in the "change import failure semantics" series.

Weinberg).  This changes all uses of deprecated tempfile functions to
the recommended ones.

imports e.g. test_support must do so using an absolute package name
such as "import test.test_support" or "from test import test_support".

This also updates the README in Lib/test, and gets rid of the
duplicate data dirctory in Lib/test/data (replaced by
Lib/email/test/data).

Now Tim and Jack can have at it. :)

allows using the tests with unittest.py as a script.  The tests will
still run when run as a script themselves.

rewrite_file():  Delete both .pyc and .pyo leftovers, and explicitly close
the new source file after writing to it.

Original by Alex Coventry (in SF patch #441791), adapted to the
standard regression test framework.