__bases__ attribute on classes not displayed by dir() command

[ast]

Hi

I have a Carre class which inherit from a Rectangle class.
Carre has a __bases__ tuple attribute which contains the
classes which it inherit from.

>>> Carre.__bases__
(<class '__main__.Rectangle'>,)

and Rectangle only inherit from object, so:

>>> Rectangle.__bases__
(<class 'object'>,)

Thats OK

but if I am using dir to display all Carre's attributes and methods,
__bases__ is not on the list. Why ?

>>> dir(Carre)
['__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__',
 '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__',
 '__init__', '__iter__', '__le__', '__lt__', '__module__', '__ne__',
 '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', 
'__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'aire', 
'count', 'long', 'perimetre', 'rotation']