code: def test_nat(self):
      primitive_instance = Season()
      primitive_func = primitive_instance.get_function()
      case = pd.Series(
          [
              "NaT",
              "2019-02",
              "2019-03",
              "NaT",
          ],
      ).astype("datetime64[ns]")
      answer = pd.Series(
          [pd.NA, "winter", "winter", pd.NA], dtype="string"
      )
      given_answer = pd.Series(primitive_func(case))
      pd.testing.assert_series_equal(given_answer, answer)
  
imports: from datetime import datetime
  import pandas
  from featuretools.primitives import Season
label_desc: Use image node_id 2 for calling the TestSeason obj's underlying member method code with example usage: obj.test_nat() without return types