code: def test_is_fixed_duration(self, frequency, expected_is_fixed):
      self.assertEqual(
          seasonality_util.is_fixed_duration(frequency),
          expected_is_fixed,
      )
  
file_path: probability/tensorflow_probability/python/sts/internal/seasonality_util_test.py
imports: from absl.testing import parameterized
  import numpy
  import pandas
  from tensorflow_probability.python.internal import test_util
  from tensorflow_probability.python.sts.internal import seasonality_util
label_desc: Use image node_id 2 for calling the SeasonalityUtilsTest obj's underlying member method code with example usage: obj.test_is_fixed_duration(frequency, expected_is_fixed) without return types