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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_ips(self, instance_id):
 """Retrieves the private and public ip addresses for a given instance. :return: list (ips) """

        self._load_instance(instance_id)
        instance = self._load_instance(instance_id)
        IPs = [ip for ip in (instance.private_ip_address, instance.ip_address) if ip]

        # We also need to check if there is any floating IP associated
        if self.request_floating_ip and not self._vpc:
            # We need to list the floating IPs for this instance
            floating_ips = [ip for ip in self._ec2_connection.get_all_addresses() if ip.instance_id == instance.id]
            if not floating_ips:
                log.debug("Public ip address has to be assigned through "
                          "elasticluster.")
                ip = self._allocate_address(instance)
                # This is probably the preferred IP we want to use
                IPs.insert(0, ip)
            else:
                IPs = [ip.public_ip for ip in floating_ips] + IPs

        return list(set(IPs))