class_docstr: Test class for first set of voting learner API tests.
code: def test_save_and_load(self):
      for learner_type, use_current_directory in product(
          ["classifier", "regressor"], [False, True]
      ):
          yield self.check_save_and_load, learner_type, use_current_directory
  
imports: import unittest
  from itertools import product
  from pathlib import Path
  import numpy
  from numpy.testing import assert_raises_regex
  from sklearn.ensemble import RandomForestRegressor, VotingClassifier, VotingRegressor
  from sklearn.linear_model import LinearRegression, LogisticRegression
  from sklearn.naive_bayes import MultinomialNB
  from sklearn.pipeline import Pipeline
  from sklearn.svm import SVC, SVR
  from skll.learner.voting import VotingLearner
  from skll.utils.testing import make_california_housing_data, make_digits_data, other_dir, output_dir
label_desc: Use image node_id 17 for calling the TestVotingLearnersAPIOne obj's underlying member method code with example usage: obj.test_save_and_load() without return types