code: def test_nans(self):
      primitive_func = self.primitive().get_function()
      times = pd.concat(
          [self.times.copy(), pd.Series([np.nan, pd.NaT])]
      )
      booleans = pd.concat(
          [self.booleans.copy(), pd.Series([np.nan], dtype="boolean")],
      )
      times = times.reset_index(drop=True)
      booleans = booleans.reset_index(drop=True)
      answer = self.cutoff_time - datetime(2011, 4, 9, 10, 31, 27)
      assert (
          primitive_func(
              times,
              booleans,
              time=self.cutoff_time,
          )
          == answer.total_seconds()
      )
  
imports: from datetime import datetime
  from math import isnan
  import numpy
  import pandas
  from featuretools.primitives import TimeSinceLastFalse, TimeSinceLastMax, TimeSinceLastMin, TimeSinceLastTrue
label_desc: Use image node_id 4 for calling the TestTimeSinceLastFalse obj's underlying member method code with example usage: obj.test_nans() without return types