code: def test_random_trend(close_figures):
      run_ucm("random_trend")
      run_ucm("random_trend", use_exact_diffuse=True)
  
imports: import warnings
  import numpy
  from numpy.testing import assert_equal, assert_allclose, assert_raises
  import pandas
  import pytest
  from statsmodels.datasets import macrodata
  from statsmodels.tools.sm_exceptions import SpecificationWarning
  from statsmodels.tsa.statespace import structural
  from statsmodels.tsa.statespace.structural import UnobservedComponents
  from statsmodels.tsa.statespace.tests.results import results_structural
label_desc: Use image node_id 14 for calling a global function with example usage: test_random_trend(close_figures) without return types