problem converting code to snippet... please help!

<?php

$ypp_feed_url = "http://gdata.youtube.com/feeds/playlists/4A4F1225777AD974";

$ypp_video_width=300;
$ypp_video_height=251;

$ypp_headline_key = "*FEED*ENTRY*TITLE"; //custom title
$ypp_description_key = "*FEED*ENTRY*YT:DESCRIPTION"; //custom description
$ypp_original_title = "*FEED*ENTRY*MEDIA:GROUP*MEDIA:TITLE";//original title ATTRIBUTE
$ypp_original_description_key = "*FEED*ENTRY*MEDIA:GROUP*MEDIA:DESCRIPTION"; //original description ATTRIBUTE
$ypp_player_url_key = "*FEED*ENTRY*MEDIA:GROUP*MEDIA:PLAYER"; //player url ATTRIBUTE
$ypp_player_entry_key = "*FEED*ENTRY"; //EACH VIDEO IS IN ONE ENTRY WRAPPER

$ypp_video_array = array();
$ypp_counter = 0;
$output = ''; //final output


function ypp_showVideo($url){
	global $ypp_video_width, $ypp_video_height;

	$t=explode("=", $url);
	$file = $t[1];

	$out = '<object width="'.$ypp_video_width.'" height="'.$ypp_video_height.'">
	  <param name="movie" value="http://www.youtube.com/v/'.$file.'" />
	  <param name="wmode" value="transparent" />
	  <embed src="http://www.youtube.com/v/'.$file.'&color1=0x5d1719&color2=0xcd311b&border=1" width="'.$ypp_video_width.'" height="'.$ypp_video_height.'" type="application/x-shockwave-flash" wmode="transparent" />
	</object>';

		return $out;
}

function ypp_startTag($ypp_parser, $ypp_data, $ypp_attributes){
    global $ypp_current_tag, $ypp_counter, $ypp_video_array;
	global $ypp_player_entry_key, $ypp_player_url_key;

    $ypp_current_tag .= "*$ypp_data";

	if($ypp_current_tag == $ypp_player_url_key){
			$ypp_video_array[$ypp_counter]['player_url'] =  $ypp_attributes['URL'];
	}
}
function ypp_endTag($ypp_parser, $ypp_data){
    global $ypp_current_tag, $ypp_counter, $ypp_player_entry_key;

    if($ypp_current_tag == $ypp_player_entry_key){
		$ypp_counter++;
	}
    $tag_key = strrpos($ypp_current_tag, '*');
    $ypp_current_tag = substr($ypp_current_tag, 0, $tag_key);
}
function ypp_contents($ypp_parser, $ypp_data){
    global $ypp_current_tag;
	global $ypp_player_url_key, $ypp_headline_key;
	global $ypp_description_key, $ypp_counter;
	global $ypp_video_array, $ypp_original_title_key;
	global $ypp_original_description_key, $ypp_player_entry_key;

    switch($ypp_current_tag){
    	case $ypp_player_entry_key:
    		break;
            $ypp_video_array[$ypp_counter]['headline'] = $ypp_data;
            break;
        case $ypp_original_title:
            $ypp_video_array[$ypp_counter]['original_title'] = $ypp_data;
            break;
        case $ypp_original_description_key:
            $ypp_video_array[$ypp_counter]['original_description'] = $ypp_data;
            break;
        case $ypp_description_key:
            $ypp_video_array[$ypp_counter]['description'] = $ypp_data;
            break;
    }
}

	$ypp_parser = xml_parser_create();
	xml_set_element_handler($ypp_parser, 'ypp_startTag', 'ypp_endTag');
	xml_set_character_data_handler($ypp_parser, 'ypp_contents');
	if( !($ypp_datastream = fopen($ypp_feed_url, 'r'))){
		$output .='<p>Could not open file</p>';
	}
	if ( !($ypp_data = stream_get_contents($ypp_datastream) )){
		$output .='<p>Could not read file</p>';
	}
	if( !(xml_parse($ypp_parser, $ypp_data, feof($ypp_datastream) ) ) ){
		$output .= '<p>Error on line ' . xml_get_current_line_number($ypp_parser) .'</p>' ;
	}
	fclose($ypp_datastream);

$output .= "\n";

for($x=0; $x < count($ypp_video_array); $x++){

	if($ypp_video_array[$x]['description'] != ""){
		$ypp_t_desc = $ypp_video_array[$x]['description'];
	}else{
		$ypp_t_desc = $ypp_video_array[$x]['original_description'];
	}
	if($ypp_video_array[$x]['headline'] != ""){
		$ypp_t_title = $ypp_video_array[$x]['headline'];
	}else{
    	$ypp_t_title = $ypp_video_array[$x]['original_title'];
	}
	$ypp_t_video = ypp_showVideo($ypp_video_array[$x]['player_url']);


	$output_chunkArr = array('video' => $ypp_t_video,'title' => $ypp_t_title,'description' => $ypp_t_desc);

        $output .= $modx->parseChunk('YouTubePlaylist', $output_chunkArr, '[+', '+]');

}//end for

      return $output;
?>

	$output_chunkArr = array('video' => $ypp_t_video,'title' => $ypp_t_title,'description' => $ypp_t_desc);
        $output .= $modx->parseChunk('YouTubePlaylist', $output_chunkArr, '[+', '+]');

global $modx;

global