Message1008

You can't correctly subclass str in 2.2a1. Instances of
the subclass are actually strings. Here is a simple
example:

>>> class p(str):
...   def foo(self):
...     print 'I am a p'
...
>>> s=p('bar')
>>> s
'bar'
>>> s.foo()
Traceback (innermost last):
 File "<console>", line 1, in ?
AttributeError: 'string' object has no attribute 'foo'
>>> type(s)
<type 'str'>

In Python 2.4.1 I get:
>>> class p(str):
...   def foo(self):
...     print 'I am a p'
...
>>> s = p('bar')
>>> s
'bar'
>>> s.foo()
I am a p
>>> type(s)
<class '__main__.p'>