def METHOD_NAME(self, mobile_user_and_group_slugs):
    if (
        EMWF.no_filters_selected(mobile_user_and_group_slugs)
        and self.request.couch_user.has_permission(self.domain, 'access_all_locations')
    ):
        return None
    user_ids = (EMWF.user_es_query(self.domain,
                                   mobile_user_and_group_slugs,
                                   self.request.couch_user)
                .values_list('_id', flat=True))
    if HQUserType.UNKNOWN in EMWF.selected_user_types(mobile_user_and_group_slugs):
        user_ids.append(SYSTEM_USER_ID)
    return form_es.user_id(user_ids)