inherrited private class varriables

[Uwe Mayer]

hi,

why can't i access a class private varriable from within a predecessor?
f.e.

class parent:
  __length = 5
  def __init__(self): pass
  def action(self):
    print self.__class__.__length

class child(parent):
  __length = 10
  def __init__(self): pass

test = child()
test.action()

will print 5, instead of 10. why?

Ciao
Uwe