SMTP in WordPress

define( 'SMTP_USER',   'user@example.com' );
define( 'SMTP_PASS',   'smtp password' );
define( 'SMTP_HOST',   'smtp.example.com' );
define( 'SMTP_FROM',   'website@example.com' );
define( 'SMTP_NAME',   'e.g Website Name' );
define( 'SMTP_PORT',   '25' );
define( 'SMTP_SECURE', 'tls' );
define( 'SMTP_AUTH',    true );
define( 'SMTP_DEBUG',   0 );

add_action( 'phpmailer_init', 'send_smtp_email' );
function send_smtp_email( $phpmailer ) {
    $phpmailer->isSMTP();
    $phpmailer->Host       = SMTP_HOST;
    $phpmailer->SMTPAuth   = SMTP_AUTH;
    $phpmailer->Port       = SMTP_PORT;
    $phpmailer->Username   = SMTP_USER;
    $phpmailer->Password   = SMTP_PASS;
    $phpmailer->SMTPSecure = SMTP_SECURE;
    $phpmailer->From       = SMTP_FROM;
    $phpmailer->FromName   = SMTP_NAME;
}