code: def test_unshift_target_factors(
      sequence, fill_with, expected_sequence
  ):
      sequence = sockeye.inference._unshift_target_factors(
          sequence, fill_last_with=fill_with
      )
      assert sequence == expected_sequence
  
imports: import itertools
  import json
  from math import ceil
  from unittest.mock import patch, Mock
  import numpy
  import pytest
  import torch
  import sockeye.beam_search
  import sockeye.constants
  import sockeye.data_io
  import sockeye.inference
  import sockeye.lexicon
  import sockeye.model
  import sockeye.utils
label_desc: Use image node_id 17 for calling a global function with example usage: test_unshift_target_factors(sequence, fill_with, expected_sequence) without return types