Python allows for private class members with the double underscore prefix.

Python allows for private class members with the double underscore prefix. This technique doesn't work at a module level so I am thinking this is a mistake in Dive Into Python.

Here is an example of private class functions:

class foo():
    def bar(self): pass
    def __bar(self): pass
    
f = foo()
f.bar()   # this call succeeds
f.__bar() # this call fails