code: def test_rows_to_columns(given, expected, wrapper):
      output = rows_to_columns(given, wrapper)
      assert_equal(output, expected)
      assert columns_to_rows(output) == given
  
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 6 for calling a global function with example usage: test_rows_to_columns(given, expected, wrapper) without return types