Filter | Type: PHPCategory Filters for Custom Post Type

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add_action( 'restrict_manage_posts', 'my_restrict_manage_posts' );
function my_restrict_manage_posts() {
    global $typenow;
    $taxonomy = $typenow.'_type';
        if( $typenow != "page" && $typenow != "post" ){
            $filters = array($taxonomy);
                foreach ($filters as $tax_slug) {
                    $tax_obj = get_taxonomy($tax_slug);
                    $tax_name = $tax_obj->labels->name;
                    $terms = get_terms($tax_slug);
                    echo "<select name='$tax_slug' id='$tax_slug' class='postform'>";
                    echo "<option value=''>Show All $tax_name</option>";
                    foreach ($terms as $term) { echo '<option value='. $term->slug, $_GET[$tax_slug] == $term->slug ? ' selected="selected"' : '','>' . $term->name .' (' . $term->count .')</option>'; }
                    echo "</select>";
               }
        }
}