code: def test_all_true(self):
      primitive_func = self.primitive().get_function()
      booleans = pd.Series([True, True, True])
      datetimes = pd.Series(
          [
              datetime(2011, 4, 9, 10, 30, i * 6)
              for i in range(len(booleans))
          ],
      )
      given_answer = primitive_func(datetimes, booleans)
      answer = pd.Series([np.nan] * 3)
      assert given_answer.equals(answer)
  
file_path: featuretools/featuretools/tests/primitive_tests/transform_primitive_tests/test_cumulative_time_since.py
imports: from datetime import datetime
  import numpy
  import pandas
  from featuretools.primitives import CumulativeTimeSinceLastFalse, CumulativeTimeSinceLastTrue
  from featuretools.tests.primitive_tests.utils import PrimitiveTestBase, find_applicable_primitives, valid_dfs
label_desc: Use image node_id 2 for calling the TestCumulativeTimeSinceLastFalse obj's underlying member method code with example usage: obj.test_all_true() without return types