See [abc] Add abstract attributes via `abstract` type-hint which has essentially this same request. Basically attributes that are not defined on the parent but which MUST be defined on the subclass. In that post I share my favorite workaround:
from abc import ABC
class Foo(ABC):
myattr: int
def __init__(self, myattr: int):
self.myattr = myattr
class Bar(Foo):
def __init__(self):
super().__init__(myattr=15)
The parent class simply has my_attr as a required constructor argument so subclasses can’t get around defining it. Though they could include my_attr as a required argument into their own constructor which is kind of like saying the subclass also has that attribute as abstract.