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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 from_jwe(self, msg, keys):
 """ Decrypt an encrypted JWT and load the JSON object that was the body of the JWT into this object. :param msg: An encrypted JWT :param keys: Possibly usable keys. :type keys: list or KeyJar instance :return: The decrypted message. If decryption failed an exception will be raised. """


        jwe = JWE()
        _res = jwe.decrypt(msg, keys)
        return self.from_json(_res.decode())