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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 get_ping(self, nonce: Nonce) -> bytes: """ Returns a signed Ping message. Note: Ping messages don't have an enforced ordering, so a Ping message with a higher nonce may be acknowledged first. """

        message = Ping(
            nonce=nonce,
            current_protocol_version=constants.PROTOCOL_VERSION,
        )
        self.raiden.sign(message)
        return message.encode()