啥是机器人！该如何解决

define('ISROBOT', getrobot());<br />if(defined('NOROBOT') && ISROBOT) {<br />	exit(header("HTTP/1.1 403 Forbidden"));<br />}<br />

function getrobot() {<br />	if(!defined('IS_ROBOT')) {<br />		$kw_spiders = 'Bot|Crawl|Spider|slurp|sohu-search|lycos|robozilla';<br />		$kw_browsers = 'MSIE|Netscape|Opera|Konqueror|Mozilla';<br />		if(preg_match("/($kw_browsers)/", $_SERVER['HTTP_USER_AGENT'])) {<br />			define('IS_ROBOT', FALSE);<br />		} elseif(preg_match("/($kw_spiders)/", $_SERVER['HTTP_USER_AGENT'])) {<br />			define('IS_ROBOT', TRUE);<br />		} else {<br />			define('IS_ROBOT', FALSE);<br />		}<br />	}<br />	return IS_ROBOT;<br />}