code: def test_reduction_names():
      x = da.ones(5, chunks=(2,))
      assert x.sum().name.startswith("sum")
      assert "max" in x.max().name.split("-")[0]
      assert x.var().name.startswith("var")
      assert x.all().name.startswith("all")
      assert any(k[0].startswith("nansum") for k in da.nansum(x).dask)
      assert x.mean().name.startswith("mean")
  
imports: from __future__ import annotations
  import os
  import warnings
  from contextlib import nullcontext
  from itertools import permutations, zip_longest
  import pytest
  import itertools
  import dask.array
  import dask.config
  from dask.array.numpy_compat import ComplexWarning, _numpy_122
  from dask.array.utils import assert_eq, same_keys
  from dask.core import get_deps
label_desc: Use image node_id 27 for calling a global function with example usage: test_reduction_names() without return types