code: def test_power_set():
      collection = list(range(4))
      subsets = list(power_set(collection))
  
      expected_subsets = [
          (),
          (0,),
          (1,),
          (2,),
          (3,),
          (0, 1),
          (0, 2),
          (0, 3),
          (1, 2),
          (1, 3),
          (2, 3),
          (0, 1, 2),
          (0, 1, 3),
          (0, 2, 3),
          (1, 2, 3),
          (0, 1, 2, 3),
      ]
  
      assert len(subsets) == 2 ** len(collection)
      assert len(expected_subsets) == 2 ** len(collection)
  
      for es in expected_subsets:
          assert es in subsets
  
imports: import itertools
  import pickle
  import tempfile
  from dataclasses import dataclass
  from pathlib import Path
  from typing import Iterable, List, Tuple
  import numpy
  from numpy.testing import assert_equal
  from toolz import take
  import pytest
  from gluonts.dataset.artificial import constant_dataset
  from gluonts.itertools import batcher, Cached, Chain, PickleCached, Cyclic, IterableSlice, SizedIterableSlice, PseudoShuffled, rows_to_columns, columns_to_rows, select, pluck_attr, power_set, Map, StarMap, Filter, join_items, RandomYield
label_desc: Use image node_id 14 for calling a global function with example usage: test_power_set() without return types