benim temamdaki kod bu özel alan resim yapmak istiyorum yardım edermisiniz

// Get image attachment (sizes: thumbnail, medium, full)
function themeloy_get_thumbnail($postid=0, $size='full') {
if ($postid<1)
$postid = get_the_ID();
$thumb = '';
if(version_compare(get_bloginfo('version'), '2.9') >= 0) {
if(!$thumb && has_post_thumbnail($postid) && function_exists( 'the_post_thumbnail' ) ) {
$post_thumbnail_id = get_post_thumbnail_id( $postid );
$image = wp_get_attachment_image_src( $post_thumbnail_id, $size );
$thumb = $image[0];
}
}

if ($thumb != null or $thumb != '') {
return $thumb;
} elseif ($images = get_children(array(
'post_parent' => $postid,
'post_type' => 'attachment',
'numberposts' => '1',
'post_mime_type' => 'image', ))) {
foreach($images as $image) {
$thumbnail=wp_get_attachment_image_src($image->ID, $size);
return $thumbnail[0];
}
}

}