get_author_mapping() public method

Map old author logins to local user IDs based on decisions made in import options form. Can map to an existing user, create a new user or falls back to the current user in case of error with either of the previous
public get_author_mapping ( )
 public function wpImportAttachments($file, $import_limit = 10)
 {
     $wp_import = new WP_Import();
     $wp_import->fetch_attachments = true;
     // load data from saved option
     $wp_import->post_orphans = get_option('_cri_post_orphans', array());
     $wp_import->processed_posts = get_option('_cri_processed_posts', array());
     $wp_import->url_remap = get_option('_cri_url_remap', array());
     add_filter('import_post_meta_key', array($wp_import, 'is_valid_meta_key'));
     add_filter('http_request_timeout', array(&$wp_import, 'bump_request_timeout'));
     // start buffer
     ob_start();
     // parse file and gather data
     $wp_import->import_start($file);
     // map author
     $wp_import->get_author_mapping();
     // attachment to be imported
     $attachments = array();
     foreach ($wp_import->posts as $post) {
         // only import attachment
         if ($post['post_type'] == 'attachment') {
             // if attachment has been imported already
             if (isset($wp_import->processed_posts[$post['post_id']]) && !empty($post['post_id'])) {
                 continue;
             }
             // if limit exceed, kill the loop
             if ($import_limit < 1) {
                 break;
             } else {
                 $import_limit--;
             }
             $attachments[] = $post;
         }
     }
     // if attachments reach to zero, we are done
     if (empty($attachments)) {
         return true;
     }
     // set importable posts to attachments
     $wp_import->posts = $attachments;
     // this process the attachments, turn off/on cache
     wp_suspend_cache_invalidation(true);
     $wp_import->process_posts();
     wp_suspend_cache_invalidation(false);
     // end has output, so buffer it out
     $wp_import->import_end();
     ob_end_clean();
     // save all post_orphans, processed_posts & url_remap to be used on the next run. also this will run on post import
     update_option('_cri_post_orphans', $wp_import->post_orphans);
     update_option('_cri_processed_posts', $wp_import->processed_posts);
     update_option('_cri_url_remap', $wp_import->url_remap);
     // false means we are going to continue
     return false;
 }