code: def test_completed_prefetch_yieldsAllCompleteUpToDefaultLimit(
      self, rayWaitMock
  ):
      # Load the pool with 1000 tasks, mock them all as complete and then
      # check that the first call to completed_prefetch only yields 999
      # items and the second call yields the final one
      pool = TaskPool()
      for i in range(1000):
          task = createMockWorkerAndObjectRef(i)
          pool.add(*task)
  
      rayWaitMock.return_value = (list(range(1000)), [])
  
      # For this test, we're only checking the object refs
      fetched = [pair[1] for pair in pool.completed_prefetch()]
      self.assertListEqual(fetched, list(range(999)))
  
      # Finally, check the next iteration returns the final taks
      fetched = [pair[1] for pair in pool.completed_prefetch()]
      self.assertListEqual(fetched, [999])
  
file_path: ray/rllib/utils/tests/test_taskpool.py
imports: import unittest
  from unittest.mock import patch
  import ray
  from ray.rllib.utils.actors import TaskPool
label_desc: Use image node_id 2 for calling the TaskPoolTest obj's underlying member method code with example usage: obj.test_completed_prefetch_yieldsAllCompleteUpToDefaultLimit(rayWaitMock) without return types