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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 _save_token_on_disk(self):
 """Helper function that saves the token on disk"""

        token = self._token.copy()

        # Client secret is needed for token refreshing and isn't returned
        # as a pared of OAuth token by default
        token.update(client_secret=self._client_secret)

        with codecs.open(config.TOKEN_FILE_PATH, 'w', 'utf8') as f:
            json.dump(
                token, f,
                ensure_ascii=False,
                sort_keys=True,
                indent=4,
            )