If the test suite is run with -3, many deprecation warnings are
reported.  Quite a few are generated by code in the tests themselves,
but many are from constructs in the stdlib which are different or no
longer supported in 3.x.

Even aside from the fact that many of these warnings being caused by
code which I think many people would agree is not ideal, I think it is
important for these warnings to be fixed for Python 2.7.  Since the 3.x
porting guidelines recommend that projects first run their test suite
with -3, these warnings are going to be generating extra noise for
developers to filter through when they try porting their code to 3.x. 
They shouldn't need to wade through stdlib warnings to find warnings
about their own code.

Attached is a log of a complete test run with -3.