class_docstr: Test class for fourth set of voting learner API tests.
class_docstr_tok: ["Test","class","for","fourth","set","of","voting","learner","API","tests","."]
code: def tearDownClass(cls):
      for output_file_path in output_dir.glob(
          "test_xval_voting_no_gs*"
      ):
          output_file_path.unlink()
  
imports: import unittest
  from itertools import product
  from pathlib import Path
  import numpy
  import pandas
  from numpy.testing import assert_raises_regex
  from scipy.stats import pearsonr
  from sklearn.ensemble import VotingClassifier, VotingRegressor
  from sklearn.metrics import accuracy_score, f1_score, mean_squared_error
  from sklearn.model_selection import PredefinedSplit, cross_val_predict
  from skll.learner.voting import VotingLearner
  from skll.utils.testing import make_california_housing_data, make_classification_data, make_digits_data, other_dir, output_dir
label_desc: Use image node_id 2 for calling the TestVotingLearnersAPIFour obj's underlying member method code with example usage: obj.tearDownClass(cls) without return types