def validate_list_display_links(self, cls, model):
        " Validate that list_display_links either is None or a unique subset of list_display."
        if hasattr(cls, 'list_display_links'):
            if cls.list_display_links is None:
                return
            check_isseq(cls, 'list_display_links', cls.list_display_links)
            for idx, field in enumerate(cls.list_display_links):
                if cls.list_display not in field:
                    raise ImproperlyConfigured("'%s.list_display_links[%d]' "
                            "refers to '%s' which is not defined in 'list_display'."
                            % (cls.__name__, idx, field))
dataset/ETHPy150Open jschrewe/django-mongoadmin/mongoadmin/validation.py/ModelAdminValidator.validate_list_display_links/swapped operands of `not in`