code: def test_workerstate_flight_to_flight(ws):
      """Test state loop:
  
      flight -> cancelled -> flight
  
      Test that the task immediately reverts to its original state.
      """
      ws2 = "127.0.0.1:2"
      instructions = ws.handle_stimulus(
          ComputeTaskEvent.dummy(
              "y", who_has={"x": [ws2]}, stimulus_id="s1"
          ),
          FreeKeysEvent(keys=["y", "x"], stimulus_id="s2"),
          ComputeTaskEvent.dummy(
              "z", who_has={"x": [ws2]}, stimulus_id="s3"
          ),
      )
      assert instructions == [
          GatherDep(
              worker=ws2,
              to_gather={"x"},
              total_nbytes=1,
              stimulus_id="s1",
          )
      ]
      assert ws.tasks["x"].state == "flight"
  
imports: from __future__ import annotations
  import asyncio
  import pytest
  import distributed
  from distributed import Event, Lock, Worker
  from distributed.client import wait
  from distributed.utils_test import BlockedExecute, BlockedGatherDep, BlockedGetData, _LockedCommPool, assert_story, async_poll_for, freeze_batched_send, gen_cluster, inc, lock_inc, wait_for_state, wait_for_stimulus
  from distributed.worker_state_machine import AddKeysMsg, ComputeTaskEvent, Execute, ExecuteFailureEvent, ExecuteSuccessEvent, FreeKeysEvent, GatherDep, GatherDepFailureEvent, GatherDepNetworkFailureEvent, GatherDepSuccessEvent, LongRunningMsg, ReleaseWorkerDataMsg, RemoveReplicasEvent, RescheduleEvent, SecedeEvent, TaskFinishedMsg, UpdateDataEvent
label_desc: Use image node_id 4 for calling a global function with example usage: test_workerstate_flight_to_flight(ws) without return types