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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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)