public static function attachToUser(Model $user, array $scopes)
	{
		$attach_scopes = [];

		foreach ($scopes as $scope) {
			$attach_scopes[] = [
				'user_id' => $user->id,
				'oauth_scope_id' => $scope,
			];
		}

		DB::table('oauth_scope_user')->insert($attach_scopes);
	}