code: def test_compression_3():
      np = pytest.importorskip("numpy")
      x = np.ones(1000000)
      frames = dumps(
          {"x": to_serialize(x.data)}, context={"compression": "zlib"}
      )
      assert sum(map(nbytes, frames)) < x.nbytes
      y = loads(frames)
      assert {"x": x.data} == y
  
imports: from __future__ import annotations
  import threading
  import zlib
  from concurrent.futures import ThreadPoolExecutor
  import pytest
  import dask.config
  from distributed import Worker, wait
  from distributed.compatibility import LINUX
  from distributed.protocol import dumps, loads, maybe_compress, msgpack, to_serialize
  from distributed.protocol.compression import Compression, compressions, get_compression_settings
  from distributed.utils import nbytes
  from distributed.utils_test import gen_cluster
label_desc: Use image node_id 7 for calling a global function with example usage: test_compression_3() without return types