mutlifile inheritance problem

[Marc]

I have classes defined in different files and would like to inherit
from a class in file A.py for a class in file B.py but am running into
problems.  I'm using Python 1.5.2 on Windows NT

Here's a specific example:

************************
file cbase01.py:

class CBase:

    def __init__(self):
        self.cclass = None
        print "cbase"

class CImStream(CBase):

    def __init(self):
        CBase.__init__(self)
        print "CImStream"

*************************
in file wrappers_A01.py: 

import cbase01
reload(cbase01)

class ImStream_SavedBitmaps(cbase01.CImStream):

    def __init__(self):
        cbase.CImStream.__init__(self)
        print "SavedBitmaps"

**************************
in file sequencer01.py

import cbase01    # the offending lines, program works 
reload(cbase01)   # if I comment these out.

class Sequencer:

    def Append(self, item):
        pass

*****************************
in test02.py

import wrappers_A01
reload(wrappers_A01)

import sequencer01
reload(sequencer01)

x0 = wrappers_A01.ImStream_SavedBitmaps()
***************************************************************

If I run test02 I get the traceback

Traceback (innermost last):
  File "<string>", line 1, in ?
  File "D:\PythonCode\pna\eyeTracking\tests\test02.py", line 15, in ?
    x0 = wrappers_A01.ImStream_SavedBitmaps()
  File "D:\PythonCode\pna\eyeTracking\tests\wrappers_A01.py", line 21,
in __init__
    cbase.CImStream.__init__(self)
TypeError: unbound method must be called with class instance 1st
argument


Any ideas what I am doing wrong?

Thanks,
Marc