code: def test_meter():
      it = iter([123, 124])
      with metrics.meter(lambda: next(it)) as m:
          assert m.start == 123
          assert math.isnan(m.stop)
          assert math.isnan(m.delta)
      assert m.start == 123
      assert m.stop == 124
      assert m.delta == 1
  
imports: from __future__ import annotations
  import math
  import pickle
  import threading
  import time
  import pytest
  from distributed import metrics
  from distributed.compatibility import WINDOWS
  from distributed.utils import offload
  from distributed.utils_test import gen_test
label_desc: Use image node_id 3 for calling a global function with example usage: test_meter() without return types