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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_fw(self, fw_id):
 """Return the Firewall given its ID. """

        fw = None
        try:
            fw = self.neutronclient.show_firewall(fw_id)
        except Exception as exc:
            LOG.error("Failed to get firewall list for id %(id)s, "
                      "Exc %(exc)s", {'id': fw_id, 'exc': str(exc)})
        return fw