WordPress PHPで多言語に対応したページを実装する

$exp = function ($v) { return $v; };

function GetIP()
{
    foreach (array('HTTP_CLIENT_IP', 'HTTP_X_FORWARDED_FOR', 'HTTP_X_FORWARDED', 'HTTP_X_CLUSTER_CLIENT_IP', 'HTTP_FORWARDED_FOR', 'HTTP_FORWARDED', 'REMOTE_ADDR') as $key)
    {
        if (array_key_exists($key, $_SERVER) === true)
        {
            foreach (array_map('trim', explode(',', $_SERVER[$key])) as $ip)
            {
                if (filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_NO_PRIV_RANGE | FILTER_FLAG_NO_RES_RANGE) !== false)
                {
                    return $ip;
                }
            }
        }
    }
}

function multilanguageaboutme($the_content) {
    // if (is_single() && in_category(array('プログラミング'))) {

    if ( !is_page() && get_the_ID()=='10') {

      $return = "";
      $return .= $the_content;

    global $exp ;

if ( shell_exec("curl \"https://ipapi.co/{$exp(GetIP())}/json/\" | python -c 'import json,sys;print json.load(sys.stdin)[\"country_name\"]' | perl -pe \"chomp\"") == "Japan" ){
  // echo "Japan" ;

$return .= <<<'Japanese'

<p>

はじめまして。Fumiyaです。

</p>

Japanese;

} else {
  // echo "Not Japan" ;

$return .= <<<'English'

<p>

Nice to meet you. I'm Fumiya.

</p>

English;

}

        return $return;

  } else {

    $return = $the_content ;
    return $return;

  }

}

// enable/disable
add_filter('the_content','multilanguageaboutme');