In [ ]:

    

class Thing(object):
    
    def __init__(self, x):
        self.x = x
    
    @property
    def x(self):
        return self._x
    
    @x.setter
    def x(self, value):
        if not isinstance(value, (int, float)):
            raise ValueError('Invalid x value!')
            
        self._x = value
        
    @property # Python decorator
    def y(self):
        return self.x**2


    

In [ ]:

    

thing = Thing(15.)


    

In [ ]:

    

print(thing.x)


    

In [ ]:

    

thing = Thing(15.)


    

In [ ]:

    

thing.y


    

In [ ]:

    

thing.x = 'sup'


    

In [ ]:

    

print(thing.x)


    

In [ ]:

    

thing.y


    

In [ ]:

    




    

In [ ]: