downcasting problem

[Tim Chase]

While a dirty hack for which I'd tend to smack anybody who used 
it...you *can* assign to instance.__class__

 >>> class A:
...     def __init__(self, name):
...             self.name = name
...     def __str__(self): return self.name
...
 >>> class B(A):
...     def foo(self): print "I'm B: %r" % self.name
...
 >>> class C(A):
...     def foo(self): print "I'm C: %r" % self.name
...
 >>> a = A("Alpha")
 >>> print a
Alpha
 >>> a.__class__
<class __main__.A at 0xb752d6bc>
 >>> a.__class__ = B
 >>> a.foo()
I'm B: 'Alpha'
 >>> a.__class__ = C
 >>> a.foo()
I'm C: 'Alpha'


If it breaks you get to keep all the parts :)

-tkc