code: def test_cupy_unsupported():
      with config.set({"array.backend": "cupy"}):
          # permutation supported for np-backed BitGenerator
          x = da.arange(12, chunks=3)
          da.random.default_rng(np.random.PCG64()).permutation(
              x
          ).compute()
  
          # permutation not supported for default cupy BitGenerator
          with pytest.raises(NotImplementedError):
              da.random.default_rng().permutation(x).compute()
  
          # choice not supported for cupy-backed Generator
          with pytest.raises(NotImplementedError):
              da.random.default_rng().choice(10).compute()
  
file_path: dask/dask/array/tests/test_cupy_random.py
imports: from __future__ import annotations
  import pytest
  import numpy
  import dask.array
  from dask import config
  from dask.array.utils import assert_eq
label_desc: Use image node_id 5 for calling a global function with example usage: test_cupy_unsupported() without return types