def METHOD_NAME(self, backup=False):
    """Save settings by pickling the settings dictionary."""
    if USERHOME is None:
        self._logger.warning("User home directory is not set, "
                             "configuration data is not saved.")
    elif isWritable(USERHOME):
        try:
            pickle(self._settings, self._rcfile, backup=backup)
        except Exception as err:
            if self._logger:
                self._logger.warning("{0} cannot write configuration "
                                     "file '{1}' ({2})."
                                     .format(self._package, self._rcfile,
                                             err))
    elif self._logger:
        self._logger.warning("{0} cannot write configuration file to "
                             "'{1}', user does not have write access."
                             .format(self._package, USERHOME))