wxPython: accessing wxFrame methods in __del__ fails

[Alex VanderWoude]

I am attempting to save my window's size and position when it closes.  So I
figured I'd put some code in the __del__() method:

from wxPython import *
class MyWindow(wxFrame):
    def __init__(self, parent, id=wxID_ANY, title=None, style=None):
        # Some stuff here.
    def __del__(self):
        x, y = self.GetPositionTuple()
        width, height = self.GetSizeTuple()
        # Store the values in a file or something.
        wxFrame.__del__(self)

However, when I run this code I end up with an unhandled exception on the
first line in __del__().  Apparently you can't call GetPositionTuple() (or
GetSizeTuple() for that matter) in __del__().  I'm confused by this, because
I thought that __del__() was called before the object was actually
destroyed.  I can still do a dir(self), so obviously not everything
associated with my instance is gone.  Or does that work because it's part of
the class, not just my instance?  Any insight into this would be greatly
appreciated.

- Alex