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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 _process_removed_port(self, device):
 """Process the removed ports."""

        LOG.debug("Trying to remove the port %r", device)
        self._update_port_status_cache(device, device_bound=False)
        self._port_unbound(device, vnic_deleted=True)

        LOG.debug("The port was successfully removed.")
        self._removed_ports.discard(device)