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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 consume(self, msg):
 """ Sign the message prior to sending the message. Args: msg (dict):
 The message to sign and relay. """

        msg['body'] = crypto.sign(msg['body'], **self.hub.config)
        super(SigningRelayConsumer, self).consume(msg)