Class variable / instance variable

[ifigazsi]

Something like this ?

class Something:
 
    data = [2, 3, 4, 5]
 
    def __init__(self):
        self.reset_data()

    def reset_data(self):
        self.data = Something.data[:]
 
something = Something()
 
something.data.append(6)
print(Something.data, something.data)
something.reset_data()
print(Something.data, something.data)

Output:
[2, 3, 4, 5] [2, 3, 4, 5, 6]
[2, 3, 4, 5] [2, 3, 4, 5]

Yes, thank you! :)
But is this a bad design or not necessarily?