code: def slot_remove_nio_binding(self, slot_number, port_number):
          
  
          try:
              adapter = self._slots[slot_number]
          except IndexError:
              raise DynamipsError('Slot {slot_number} does not exist on router "{name}"'.format(name=self._name,
                                                                                                slot_number=slot_number))
  
          if adapter is None:
              raise DynamipsError("Adapter is missing in slot {slot_number}".format(slot_number=slot_number))
  
          if not adapter.port_exists(port_number):
              raise DynamipsError("Port {port_number} does not exist in adapter {adapter}".format(adapter=adapter,
                                                                                                  port_number=port_number))
  
          yield from self.slot_disable_nio(slot_number, port_number)
          yield from self._hypervisor.send('vm slot_remove_nio_binding "{name}" {slot_number} {port_number}'.format(name=self._name,
                                                                                                                    slot_number=slot_number,
                                                                                                                    port_number=port_number))
  
          nio = adapter.get_nio(port_number)
          if nio is None:
              return
          yield from nio.close()
          adapter.remove_nio(port_number)
  
          log.info('Router "{name}" [{id}]: NIO {nio_name} removed from port {slot_number}/{port_number}'.format(name=self._name,
                                                                                                                 id=self._id,
                                                                                                                 nio_name=nio.name,
                                                                                                                 slot_number=slot_number,
                                                                                                                 port_number=port_number))
  
          return nio
docs: Removes a slot NIO binding.
  
          :param slot_number: slot number
          :param port_number: port number
  
          :returns: removed NIO instance