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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_device(self):
 """ Returns a reference to the device that is represented by this node. Returns None if no such device can be determined. """

        addr = self.address
        servers = [server for server in pyrax.cloudservers.list()
                if addr in server.networks.get("private", "")]
        try:
            return servers[0]
        except IndexError:
            return None