code: def attach_network_interface(self, network_interface_id,
                                   instance_id, device_index):
          
          params = {'NetworkInterfaceId' : network_interface_id,
                    'InstanceId' : instance_id,
                    'Deviceindex' : device_index}
          return self.get_status('AttachNetworkInterface', params, verb='POST')
docs: Attaches a network interface to an instance.
  
          :type network_interface_id: str
          :param network_interface_id: The ID of the network interface to attach.
  
          :type instance_id: str
          :param instance_id: The ID of the instance that will be attached
              to the network interface.
  
          :type device_index: int
          :param device_index: The index of the device for the network
              interface attachment on the instance.