[Python] Override property from wrapper class

I have a class A with a property prop and a method method that uses this property:

class A:
@property
def prop(self) -> int:
return 1

def method(self) -> int:
return self.prop * 2 # Uses self.prop


Then I have a wrapper class that tries to override this property like this:

class B:
def __init__(self, a: A):
self._a = a

@property
def prop(self) -> int:
return 2 # Override A's property

def __getattr__(self, attr):
if attr in self.__dict__:
return getattr(self, attr)

return getattr(self._a, attr) # Delegate attribute access to A if attr not in B


When b.method() is called, I'd like the calculation to be done with B's prop, and get 4 as result. What is happening instead is that prop is resolving within A, and b.method() returns 2.

b = B(a)

b.method() # Returns 2. Wanted 4


Is there any way I can override the property prop in A, when used on A's code, when it is being wrapped by B?

• I can't use inheritance for these classes
• I'd like to avoid replicating the method() logic in B
• I also tried setting __getattribute__ in B, but it seems it is not even called when resolving prop inside A

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