class HideX(object):
def __init__(self, x):
self.x = x
def get_x(self):
return ~self.__x
def set_x(self, x):
assert isinstance(x, int), '"x" must be an integer!'
self.__x = ~x
x = property(get_x, set_x)
inst = HideX(20)
print inst.x
inst.x = 30
print inst.x