public static function factory($region, $profile, $configuration_set, $handler=null) {
        
        $config = [
            'region' => $region,
            'profile' => $profile, 
            'http' => [
                'verify' => false//TODO: fix for production
            ],
        ];
        
        if (!is_null($configuration_set))
            $config['version'] = '2010-12-01';
        
        if (!is_null($handler))
            $config['handler'] = $handler;
        
        $client = SesClient::factory($config);
        
        return new AwsSesWrapper($client, $configuration_set);
    }