docs: def get_wrapped_instance(self, instance=None):
          """Returns a wrapped model instance.
          """
          if instance._meta.label_lower not in self.registry:
              raise ModelNotRegistered(f"{repr(instance)} is not registered with {self}.")
          wrapper_cls = self.registry.get(instance._meta.label_lower) or self.wrapper_cls
          if wrapper_cls:
              return wrapper_cls(instance)
          return instance