code: static AuthenticationResult fromPreferences(Context context) {
          SharedPreferences prefs = getPreferences(context);
          String authToken = prefs.getString(KEY_AUTH_TOKEN, null);
          String noteStoreUrl = prefs.getString(KEY_NOTESTORE_URL, null);
  
          if (TextUtils.isEmpty(authToken) || TextUtils.isEmpty(noteStoreUrl)) {
              return null;
          }
  
          return new AuthenticationResult(authToken, noteStoreUrl,
                  prefs.getString(KEY_WEB_API_URL_PREFIX, null),
                  prefs.getString(KEY_EVERNOTE_HOST, null),
                  prefs.getInt(KEY_USER_ID, -1),
                  prefs.getBoolean(KEY_IS_APP_LINKED_NOTEBOOK, false));
      }
docs: /*package