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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 create_refresh_token(identity, expires_delta=None, user_claims=None):
 """ Creates a new refresh token. :param identity: The identity of this token, which can be any data that is json serializable. It can also be a python object, in which case you can use the :meth:`~flask_jwt_extended.JWTManager.user_identity_loader` to define a callback function that will be used to pull a json serializable identity out of the object. :param expires_delta: A `datetime.timedelta` for how long this token should last before it expires. Set to False to disable expiration. If this is None, it will use the 'JWT_REFRESH_TOKEN_EXPIRES` config value (see :ref:`Configuration Options`) :param user_claims: Optionnal JSON serializable to override user claims. :return: An encoded refresh token """

    jwt_manager = _get_jwt_manager()
    return jwt_manager._create_refresh_token(identity, expires_delta, user_claims)