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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 sign(self, msg, key):
 """ Create a signature over a message as defined in RFC7515 using an RSA key :param msg: the message. :type msg: bytes :returns: bytes, the signature of data. :rtype: bytes """


        if not isinstance(key, rsa.RSAPrivateKey):
            raise TypeError(
                "The key must be an instance of rsa.RSAPrivateKey")
        sig = key.sign(msg, self.padding, self.hash)
        return sig