Error Unhandled exception in thread started by Error in sys excepthook

Question

I sometimes see the following exceptions when shutting down my app (using Python 2.5.1):

  Unhandled exception in thread started by
  Error in sys.excepthook:
  
  Original exception was:
  Exception in thread Thread-3 (most likely raised during interpreter shutdown):
  Traceback (most recent call last):
    File "/usr/local/lib/python2.5/threading.py", line 460, in __bootstrap
    File "/usr/local/lib/python2.5/threading.py", line 440, in run
    File "/home/yang/local/armed/lib/python2.5/site-packages/afx/threads.py", line 71, in worker
    File "/usr/local/lib/python2.5/Queue.py", line 176, in get
    File "/usr/local/lib/python2.5/threading.py", line 248, in notify
  <type 'exceptions.TypeError'>: exceptions must be classes, instances, or strings (deprecated), not NoneType
  Unhandled exception in thread started by
  Error in sys.excepthook:

Answer 1

I think the general idea of the problem has been stated, but I figured I
would state the official issue.  When Python begins to shutdown it takes
each module and sets each variable in the global namespace to None. If a
thread has not terminated before the interpreter terminates then the
thread tries to use a global variable which has been set to None.

This is not about to change since this occurs because of coding
"errors". You must make sure that either your thread is as safe as a
__del__ method (which means no global namespace access) or you can't let
the app exit until you are positive all of your threads have terminated,
not just asked them to shutdown since this is all asynchronous.