code: def test_get_parallel_bucket(
      buckets,
      source_length,
      target_length,
      expected_bucket_index,
      expected_bucket,
  ):
      bucket_index, bucket = data_io.get_parallel_bucket(
          buckets, source_length, target_length
      )
      assert bucket_index == expected_bucket_index
      assert bucket == expected_bucket
  
imports: import os
  import random
  from tempfile import TemporaryDirectory
  from typing import Optional, List, Tuple
  import numpy
  import pytest
  import torch
  from sockeye import constants
  from sockeye import data_io
  from sockeye import utils
  from sockeye import vocab
  from sockeye.test_utils import tmp_digits_dataset
  from sockeye.utils import SockeyeError, get_tokens, seed_rngs
label_desc: Use image node_id 20 for calling a global function with example usage: test_get_parallel_bucket(buckets, source_length, target_length, expected_bucket_index, expected_bucket) without return types