code: def test_nested_types():
      x = np.ones(5)
      header, frames = serialize([[[x]]])
      assert "dask" in str(header)
      assert len(frames) == 1
      assert x.data == np.frombuffer(frames[0]).data
  
imports: from __future__ import annotations
  import pytest
  from distributed.protocol import deserialize, serialize
label_desc: Use image node_id 3 for calling a global function with example usage: test_nested_types() without return types