code: def test_cancellation_as_completed(client):
      with client.get_executor(pure=False) as e:
          fs = [e.submit(slowinc, i, delay=0.2) for i in range(10)]
          fs[3].cancel()
          fs[8].cancel()
  
          n_cancelled = sum(
              f.cancelled() for f in as_completed(fs, timeout=30)
          )
          assert n_cancelled == 2
  
imports: from __future__ import annotations
  import random
  from concurrent.futures import FIRST_COMPLETED, FIRST_EXCEPTION, Future, TimeoutError, as_completed, wait
  from time import sleep
  import pytest
  from tlz import take
  from distributed.event import Event
  from distributed.metrics import time
  from distributed.utils import CancelledError
  from distributed.utils_test import inc, slowadd, slowinc, throws, varying
label_desc: Use image node_id 7 for calling a global function with example usage: test_cancellation_as_completed(client) without return types