public function update( $type, $item ) {
    $skin = new Automatic_Upgrader_Skin;

    switch ( $type ) {
      case 'core':
        // The Core upgrader doesn't use the Upgrader's skin during the actual main part of the upgrade, instead, firing a filter.
        add_filter( 'update_feedback', array( $skin, 'feedback' ) );
        $upgrader = new Core_Upgrader( $skin );
        $context  = ABSPATH;
        break;
      case 'plugin':
        $upgrader = new Plugin_Upgrader( $skin );
        $context  = WP_PLUGIN_DIR; // We don't support custom Plugin directories, or updates for WPMU_PLUGIN_DIR.
        break;
      case 'theme':
        $upgrader = new Theme_Upgrader( $skin );
        $context  = get_theme_root( $item->theme );
        break;
      case 'translation':
        $upgrader = new Language_Pack_Upgrader( $skin );
        $context  = WP_CONTENT_DIR; // WP_LANG_DIR;
        break;
    }

    // Determine whether we can and should perform this update.
    if ( ! $this->WP_Automatic_Updater::should_update( $type, $item, $context ) ) {
      return false;
    }

    
/**
 * Fires immediately prior to an auto-update.
 *
 * @since 4.4.0
 *
 * @param string $type    The type of update being checked: 'core', 'theme', 'plugin', or 'translation'.
 * @param object $item    The update offer.
 * @param string $context The filesystem context (a path) against which filesystem access and status
 *                        should be checked.
 */
    do_action( 'pre_auto_update', $type, $item, $context );

    $upgrader_item = $item;
    switch ( $type ) {
      case 'core':
        /* translators: %s: WordPress version. */
        $skin->feedback( __( 'Updating to WordPress %s' ), $item->version );
        /* translators: %s: WordPress version. */
        $item_name = sprintf( __( 'WordPress %s' ), $item->version );
        break;
      case 'theme':
        $upgrader_item = $item->theme;
        $theme         = wp_get_theme( $upgrader_item );
        $item_name     = $theme->Get( 'Name' );
        // Add the current version so that it can be reported in the notification email.
        $item->current_version = $theme->get( 'Version' );
        if ( empty( $item->current_version ) ) {
          $item->current_version = false;
        }
        /* translators: %s: Theme name. */
        $skin->feedback( __( 'Updating theme: %s' ), $item_name );
        break;
      case 'plugin':
        $upgrader_item = $item->plugin;
        $plugin_data   = get_plugin_data( $context . '/' . $upgrader_item );
        $item_name     = $plugin_data['Name'];
        // Add the current version so that it can be reported in the notification email.
        $item->current_version = $plugin_data['Version'];
        if ( empty( $item->current_version ) ) {
          $item->current_version = false;
        }
        /* translators: %s: Plugin name. */
        $skin->feedback( __( 'Updating plugin: %s' ), $item_name );
        break;
      case 'translation':
        $language_item_name = $upgrader->get_name_for_update( $item );
        /* translators: %s: Project name (plugin, theme, or WordPress). */
        $item_name = sprintf( __( 'Translations for %s' ), $language_item_name );
        /* translators: 1: Project name (plugin, theme, or WordPress), 2: Language. */
        $skin->feedback( sprintf( __( 'Updating translations for %1$s (%2$s)…' ), $language_item_name, $item->language ) );
        break;
    }

    $allow_relaxed_file_ownership = false;
    if ( 'core' === $type && isset( $item->new_files ) && ! $item->new_files ) {
      $allow_relaxed_file_ownership = true;
    }

    // Boom, this site's about to get a whole new splash of paint!
    $upgrade_result = $upgrader->upgrade(
      $upgrader_item,
      array(
        'clear_update_cache'           => false,
        // Always use partial builds if possible for core updates.
        'pre_check_md5'                => false,
        // Only available for core updates.
        'attempt_rollback'             => true,
        // Allow relaxed file ownership in some scenarios.
        'allow_relaxed_file_ownership' => $allow_relaxed_file_ownership,
      )