belongsTo(User::class, 'user_id'); } public function AAGUID() { $guid = $this->AAGUID; return sprintf( '%s-%s-%s-%s-%s', substr($guid, 0, 8), substr($guid, 8, 4), substr($guid, 12, 4), substr($guid, 16, 4), substr($guid, 20, 12) ); } }