code: def test_uv_feature_functions():
      """test feature functions with univariate data"""
      N = 20
      W = 30
      uv_data = np.random.rand(N, W)
  
      ftr_funcs = {}
      ftr_funcs.update(feature_functions.all_features())
      ftr_funcs.update(feature_functions.base_features())
      ftr_funcs.update(feature_functions.hudgins_features())
      ftr_funcs.update(feature_functions.emg_features())
  
      for f in ftr_funcs:
          uvf = ftr_funcs[f](uv_data)
          assert len(uvf) == N
  
label_desc: Use image node_id 2 for calling a global function with example usage: test_uv_feature_functions() without return types