antiprivate.py

In [1]: class Foo: 
   ...:     def __init__(self): 
   ...:         exec("self.__bar = 'hello'") 
   ...:     def bar(self): 
   ...:         print(self.__bar) 
   ...:                                                                                                                                                                                                                                       

In [2]: foo = Foo()                                                                                                                                                                                                                           

In [3]: foo.__bar                                                                                                                                                                                                                             
Out[3]: 'hello'

In [4]: foo.bar()                                                                                                                                                                                                                             
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-4-8b3beb1ccf05> in <module>
----> 1 foo.bar()

<ipython-input-1-3b5b82ebc0e7> in bar(self)
      3         exec("self.__bar = 'hello'")
      4     def bar(self):
----> 5         print(self.__bar)
      6 

AttributeError: 'Foo' object has no attribute '_Foo__bar'