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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 fetch_by_code(self, code):
 """ Returns data belonging to an authorization code from memcache or ``None`` if no data was found. See :class:`oauth2.store.AuthCodeStore`. """

        code_data = self.mc.get(self._generate_cache_key(code))

        if code_data is None:
            raise AuthCodeNotFound

        return AuthorizationCode(**code_data)