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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 add_probe(self, probe):
 """Adds a Probe instance to this hop's results."""

        if self.probes:
            probe_last = self.probes[-1]
            if not probe.ip:
                probe.ip = probe_last.ip
                probe.name = probe_last.name
        self.probes.append(probe)