code: def test_nat():
      date_to_holiday = DateToHoliday()
      case = pd.Series(
          [
              "2019-10-14",
              "NaT",
              "2016-02-15",
              "NaT",
          ],
      ).astype("datetime64[ns]")
      answer = ["Columbus Day", np.nan, "Washington's Birthday", np.nan]
      given_answer = date_to_holiday(case).astype("str")
      np.testing.assert_array_equal(given_answer, answer)
  
file_path: featuretools/featuretools/tests/primitive_tests/transform_primitive_tests/test_datetoholiday_primitive.py
imports: from datetime import datetime
  import numpy
  import pandas
  import pytest
  from featuretools.primitives import DateToHoliday
label_desc: Use image node_id 3 for calling a global function with example usage: test_nat() without return types