code: def test_leaf_no_time_index(self, es):
      es.add_last_time_indexes()
      stores = es["stores"]
      true_lti = pd.Series(
          [None for x in range(6)], dtype="datetime64[ns]"
      )
  
      assert len(true_lti) == len(stores[LTI_COLUMN_NAME])
  
      stores_lti = to_pandas(stores[LTI_COLUMN_NAME])
  
      for v1, v2 in zip(stores_lti, true_lti):
          assert (pd.isnull(v1) and pd.isnull(v2)) or v1 == v2
  
imports: from datetime import datetime
  import pandas
  import pytest
  from woodwork.logical_types import Categorical, Datetime, Integer
  from featuretools.entityset.entityset import LTI_COLUMN_NAME
  from featuretools.tests.testing_utils import to_pandas
  from featuretools.utils.gen_utils import Library, import_or_none
label_desc: Use image node_id 2 for calling the TestLastTimeIndex obj's underlying member method code with example usage: obj.test_leaf_no_time_index(es) without return types