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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:
 async def generate_access_token(self, user):
 """ Generate an access token for a given user. """

        payload = await self._get_payload(user)
        secret = self._get_secret(True)
        algorithm = self._get_algorithm()

        return jwt.encode(payload, secret, algorithm=algorithm).decode("utf-8")