foo.py

try:
    from typing import Protocol
except ImportError:
    from typing_extensions import Protocol


class A:
    pass


class B:
    __slots__ = ()


class C(B):
    pass


class D(C):
    pass


class E(B):
    __slots__ = ("a", "b")


class F(E):
    __slots__ = ()


class G(F):
    __slots__ = ("k", "j")


class H:
    __slots__ = {"k": "something", "z": "else"}


class J(H):
    __slots__ = ["j", "a"]


class K(H):
    __slots__ = {"j", "a"}


class L(D):
    pass


class M(zip):
    __slots__ = ()


class N(zip):
    __slots__ = ("a", "b")


class P(int):
    __slots__ = ()


class Q(B, H):
    __slots__ = ("w",)


class R(Q):
    pass


class S(R):
    __slots__ = ()


class U(L):
    __slots__ = ("o", "p")

    class Ua(Q):
        __slots__ = ("i", "w")

    class Ub(Ua):
        __slots__ = "w"


class T(A):
    __slots__ = {"z", "r"}


class V(U):
    __slots__ = ("v",)


class W(V):
    __slots__ = {"p": "", "q": "", "v": ""}


class X(RuntimeError):
    pass


class Z:
    __slots__ = ("a", "b", "c", "b", "b", "c")


class Za(Z):
    __slots__ = ("b", "c")


class MyProto(Protocol):
    pass


class Zb(MyProto):
    __slots__ = ()