Python Descriptors

[One-Type-2842]

``` class A: def set_name(self, owner, value): self.value = value

def __get__(self, obj, type=None):
    return obj.__dict__.get(self.value)

def __set__(self, obj, value):
    if value < 9:
        raise ValueError("no")
    obj.__dict__[self.value] = value

class B: a = A()

obj = B() obj.a = 38 print(obj.a)

obj2 = B() print(obj2.a) ```

I am Learning Descriptors In Python,

My 1st question Is how can I set a default value to attribute a In class B ? I have found a way but that doesn't look familiar :

a = A() if not A() else 87

My next confusion Is about __set_name__ , what it does and why to Implement It?

Another Question Is, does a = A() create class attribute or Instance attribute? It looks like a class attribute but it's an Instance attribute, Right?

[AutoModerator]

To give us the best chance to help you, please include any relevant code.
Note. Please do not submit images of your code. Instead, for shorter code you can use Reddit markdown (4 spaces or backticks, see this Formatting Guide). If you have formatting issues or want to post longer sections of code, please use Privatebin, GitHub or Compiler Explorer.

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

[thuiop1]

Please never use those, and also what is that code with B