I have to wonder why you’d want something like this to be in the language. Although you can make this kinda thing happen with metaclasses and such like mentioned here, this is a complex behavior that would be difficult to explain to someone that wasn’t intimately familiar with the details.
I have to wonder…why not just try to simplify how you do your __init__ methods and make them more independent? This isn’t C++; you don’t have to allocate a ton of resources just to make an object. And as mentioned above, Python style typically prefers a more explicit way of handing those things when you need it. What problem are you trying to solve (at a higher level than “make the language act like I want it to”)? Perhaps there’s a more idiomatic way of approaching it