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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 HandleForwardedIps(self, interface, forwarded_ips, interface_ip=None):
 """Handle changes to the forwarded IPs on a network interface. Args: interface: string, the output device to configure. forwarded_ips: list, the forwarded IP address strings desired. interface_ip: string, current interface ip address. """

    desired = self.ip_forwarding_utils.ParseForwardedIps(forwarded_ips)
    configured = self.ip_forwarding_utils.GetForwardedIps(
        interface, interface_ip)
    to_add = sorted(set(desired) - set(configured))
    to_remove = sorted(set(configured) - set(desired))
    self._LogForwardedIpChanges(
        configured, desired, to_add, to_remove, interface)
    self._AddForwardedIps(to_add, interface)
    self._RemoveForwardedIps(to_remove, interface)