Problem with __del__

[Stephan Effelsberg]

I have the following code:

def dosomething():
  print "doing something"

class Nothing:
  def __init__(self, name):
    self.name=name
  def __del__(self):
    print self.name, dosomething
    dosomething()

cl=Nothing("cl")
nothing=Nothing("nothing")
cla=Nothing("cla")
cl2=Nothing("cl2")


When running this (Python 1.5.2 on Win95) I get the following output:

cl2 <function dosomething at 8a7c90>
doing something
cla <function dosomething at 8a7c90>
doing something
cl <function dosomething at 8a7c90>
doing something
nothing None
Exception exceptions.TypeError: 'call of non-function (type None)' in
<method Nothing.__del__ of Nothing instance at 8a7f60> ignored

Everything works properly except for 'nothing'.
Now I swapped the lines for instanciating 'cl' and 'nothing' with the
following result:

cl2 <function dosomething at 8a7c90>
doing something
cla <function dosomething at 8a7c90>
doing something
nothing None
Exception exceptions.TypeError: 'call of non-function (type None)' in
<method Nothing.__del__ of Nothing instance at 8a7ee0> ignored
cl None
Exception exceptions.TypeError: 'call of non-function (type None)' in
<method Nothing.__del__ of Nothing instance at 8a7f60> ignored

Now it seems that both 'nothing' and 'cl' aren't able to see the
function dosomething().

Can somebody explain this phenomenon?
Is it a special bug of my specific Python distribution?