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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 to_jwt(self, key=None, algorithm="", lev=0, lifetime=0):
 """ Create a signed JWT representation of the class instance :param key: The signing key :param algorithm: The signature algorithm to use :param lev: :param lifetime: The lifetime of the JWS :return: A signed JWT """


        _jws = JWS(self.to_json(lev), alg=algorithm)
        return _jws.sign_compact(key)