def _get_last_cachefile_modification(self):
        """
        Get last modification of cache file with TLDs.

        :return: Date and time of last modification or
                 None when file does not exist
        :rtype: datetime|None
        """

        try:
            mtime = os.path.getmtime(self._tld_list_path)
        except OSError:
            return None

        return datetime.fromtimestamp(mtime)
Get last modification of cache file with TLDs.

        :return: Date and time of last modification or
                 None when file does not exist
        :rtype: datetime|None