@cached_classmethod
    def target_models(cls):
        if cls.page_type:
            target_models = []

            for page_type in cls.page_type:
                try:
                    target_models.append(resolve_model_string(page_type))
                except LookupError:
                    raise ImproperlyConfigured(
                        "{0}.page_type must be of the form 'app_label.model_name', given {1!r}".format(
                            cls.__name__, page_type
                        )
                    )
                except __HOLE__:
                    raise ImproperlyConfigured(
                        "{0}.page_type refers to model {1!r} that has not been installed".format(
                            cls.__name__, page_type
                        )
                    )

            return target_models
        else:
            return [cls.model._meta.get_field(cls.field_name).rel.to]
dataset/ETHPy150Open torchbox/wagtail/wagtail/wagtailadmin/edit_handlers.py/BasePageChooserPanel.target_models