def test_dataclass_derived_generic_from_slotted_base(self):
    T = typing.TypeVar('T')

    class WithSlots:
        __slots__ = ('a', 'b')

    @dataclass(slots=True, weakref_slot=True)
    class E1(WithSlots, Generic[T]):
        pass
...
def test_dataclass_derived_generic_from_slotted_base(self):
    T = typing.TypeVar('T')

    class WithWeakrefSlot:
        __slots__ = ('__weakref__',)

    @dataclass(slots=True, weakref_slot=True)
    class G1(WithWeakrefSlot, Generic[T]):
        pass