code: def test_explicit_base_component(self):
      series = self._build_test_series(
          shape=[48], freq=pd.DateOffset(hours=1)
      )
      model = default_model.build_default_model(
          series,
          base_component=semilocal_linear_trend.SemiLocalLinearTrend(
              level_scale_prior=exponential.Exponential(5.0),
              slope_scale_prior=exponential.Exponential(0.1),
              slope_mean_prior=normal.Normal(0.0, 100.0),
              constrain_ar_coef_positive=True,
              constrain_ar_coef_stationary=True,
              observed_time_series=series,
          ),
      )
      self.assertLen(model.components, 2)
  
      param_by_name = lambda n: [
          p for p in model.parameters if n in p.name
      ][0]
      self.assertAllClose(param_by_name("level_scale").prior.rate, 5.0)
      self.assertAllClose(
          param_by_name("slope_mean").prior.scale, 100.0
      )
      self.assertAllClose(param_by_name("slope_scale").prior.rate, 0.1)
  
imports: import pandas
  import tensorflow.compat.v2
  from tensorflow_probability.python.distributions import exponential
  from tensorflow_probability.python.distributions import normal
  from tensorflow_probability.python.internal import test_util
  from tensorflow_probability.python.internal import tf_keras
  from tensorflow_probability.python.optimizer.convergence_criteria import successive_gradients_are_uncorrelated
  from tensorflow_probability.python.sts import default_model
  from tensorflow_probability.python.sts import fitting
  from tensorflow_probability.python.sts import regularization
  from tensorflow_probability.python.sts.components import local_linear_trend
  from tensorflow_probability.python.sts.components import seasonal
  from tensorflow_probability.python.sts.components import semilocal_linear_trend
  from tensorflow_probability.python.sts.components import sum
  from tensorflow_probability.python.sts.forecast import forecast
  from tensorflow_probability.python.vi import optimization
label_desc: Use image node_id 3 for calling the DefaultModelTests obj's underlying member method code with example usage: obj.test_explicit_base_component() without return types