code: def test_percentiles_with_unknown_chunk_sizes():
      rng = da.random.default_rng(cupy.random.default_rng())
      x = rng.random(1000, chunks=(100,))
      x._chunks = ((np.nan,) * 10,)
  
      result = da.percentile(x, 50, method="midpoint").compute()
      assert type(result) == cupy.ndarray
      assert 0.1 < result < 0.9
  
      a, b = da.percentile(x, [40, 60], method="midpoint").compute()
      assert type(a) == cupy.ndarray
      assert type(b) == cupy.ndarray
      assert 0.1 < a < 0.9
      assert 0.1 < b < 0.9
      assert a < b
  
file_path: dask/dask/array/tests/test_cupy_percentile.py
imports: from __future__ import annotations
  import numpy
  import pytest
  import dask.array
  from dask.array.utils import assert_eq, same_keys
label_desc: Use image node_id 6 for calling a global function with example usage: test_percentiles_with_unknown_chunk_sizes() without return types