[issue6242] Fix reference leak in io.StringIO

[Antoine Pitrou]

Antoine Pitrou <pitrou at free.fr> added the comment:

Why do you need all this? Isn't it enough to take a weakref and check
the callback is triggered?
(besides, we should avoid tests which only work in debug mode)

----------

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue6242>
_______________________________________