code: def test_merge_list_left_bigger(self):
      a, b = [1, 2], [3]
      result = combiners._merge_list(a, b)
      self.assertEqual(result, [1, 2, 3])
      self.assertIs(result, a)
  
imports: import dataclasses
  import numpy
  from absl.testing import absltest
  from absl.testing import parameterized
  from unittest.mock import patch
  from typing import Tuple
  import pipeline_dp
  from analysis import per_partition_combiners
  from analysis import metrics
  from analysis.tests import common
label_desc: Use image node_id 1 for calling the UtilitiesTest obj's underlying member method code with example usage: obj.test_merge_list_left_bigger() without return types