[Python] Using @property to clone attributes initialized from superclass

I want to create a class inheriting from a superclass that keeps track of the already initialized class attributes in the superclass. The @property decorator caught my eye and I tried to implement it (see example below).

class MyClass():

def __init__(self):
self.data = 'myinitialdata'

class MySubClass(MyClass):

def __init__(self, myclass):
super().__init__()
self._myclass = myclass

@property
def data(self):
return self._myclass.data

def main():
new_myclass = MyClass()
new_myclass.data = 'mynewdata'
new_mysubclass = MySubClass(new_myclass)

print(new_mysubclass.data)

if __name__=='__main__':
main()


However, if I want to create a property of an already initialized attribute (in the superclass) I always receive an error that the attribute cannot be set:

AttributeError: can't set attribute 'data'


The code example works if I do not initialize data in MyClass:

class MyClass():

def __init__(self):
# self.data = 'myinitialdata'
pass

class MySubClass(MyClass):

def __init__(self, myclass):
super().__init__()
self._myclass = myclass

@property
def data(self):
return self._myclass.data

def main():
new_myclass = MyClass()
new_myclass.data = 'mynewdata'
new_mysubclass = MySubClass(new_myclass)

print(new_mysubclass.data)

if __name__=='__main__':
main()


Output:

mynewdata


Am I misusing the @property decorator here or am I missing something else in my implementation? Is the @property decorator meant to be used in that kind of scenario?

I am currently using Python 3.10.9

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