@Override
    public boolean isAssignableFrom(@NotNull Exact other) {
      if (equals(other) || other instanceof Unresolved) return true;
      if (other instanceof ExactClass exactClass) {
        return exactClass.classDef.isInheritor(classDef);
      }
      if (other instanceof ExactSubclass subclass) {
        for (Exact superClass : subclass.mySupers) {
          if (isAssignableFrom(superClass)) return true;
        }
      }
      return false;
    }
@Override
    public boolean isAssignableFrom(@NotNull Exact other)