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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 set_is_success(self, last_hop):
 """Sets the flag if traceroute result is successful or not."""

        for packet in last_hop.packets:
            if packet.rtt and not packet.is_error:
                self.is_success = True
                break
        else:
            self.set_last_hop_errors(last_hop)