>>> class A():
...     x = 5
...     def __init__(self):
...         self.y = 7
...
... class C(A):
...     cx = 15
...     def __init__(self):
...         self.cy = 17
...
... cc = C()

>>> cc.cy
17

>>> cc.y
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'C' object has no attribute 'y'
'C' object has no attribute 'y'

>>> cc.cx
15

>>> cc.x
5

>>>