code: def test_itemsize(dt, size):
      assert itemsize(np.dtype(dt)) == size
  
imports: from __future__ import annotations
  from zlib import crc32
  import pytest
  from dask.utils import ensure_bytes, tmpfile
  from distributed.protocol import decompress, deserialize, dumps, loads, msgpack, serialize, to_serialize
  from distributed.protocol.compression import maybe_compress
  from distributed.protocol.numpy import itemsize
  from distributed.protocol.utils import BIG_BYTES_SHARD_SIZE
  from distributed.system import MEMORY_LIMIT
  from distributed.utils import nbytes
  from distributed.utils_test import gen_cluster
label_desc: Use image node_id 9 for calling a global function with example usage: test_itemsize(dt, size) without return types