[Tutor] Trouble with "RuntimeError: underlying C/C++ object has been deleted".

[Lawrence Shafer]

Hello List,

I am just learning Python/PyQt4, and have a problem I cannot figure out.
Here's what happens.

Traceback (most recent call last):
    File "iac.py", line 124, in on_actionOpen_triggered
      self.open()
    File "iac.py", line 66, in open
      if self.isUntitled and self.textBrowser.document().isEmpty() and not
self.isWindowModified():
RuntimeError: underlying C/C++ object has been deleted


I have copied several parts of other programs, so that's probably where
this is coming from. All I want is to load a .txt file into
self.textBrowser, so some of the functionality is unneeded at this time,
except for filter saving and loading. If someone understands what is
going on, that would be great!

The source can be downloaded from here 
http://lawrence.orbwireless.net/iac_src.tar.gz

Thanks!
Lawrence