class_docstr: Test class for output tests.
docstr: Test to check learning curve raises error with less than 500 examples.
docstr_tok: ["Test","to","check","learning","curve","raises","error","with","less","than","500","examples","."]
code: def test_learning_curve_min_examples_check(self):
      """Test to check learning curve raises error with less than 500 examples."""
      # generates a training split with less than 500 examples
      train_fs_less_than_500, _ = make_classification_data(
          num_examples=499, train_test_ratio=1.0, num_labels=3
      )
  
      # creating an example learner
      learner = Learner("LogisticRegression")
  
      # this must throw an error because `examples` has less than 500 items
      with self.assertRaises(ValueError):
          _ = learner.learning_curve(
              examples=train_fs_less_than_500, metric="accuracy"
          )
  
imports: import csv
  import json
  import re
  import unittest
  import warnings
  from ast import literal_eval
  from collections import defaultdict
  from itertools import chain, product
  from pathlib import Path
  from unittest.mock import Mock, patch
  import numpy
  import pandas
  from numpy.testing import assert_almost_equal, assert_array_almost_equal, assert_array_equal
  from sklearn.model_selection import ShuffleSplit, learning_curve
  from sklearn.naive_bayes import MultinomialNB
  from skll.data import FeatureSet, NDJReader, NDJWriter, Reader
  from skll.experiments import run_configuration
  from skll.experiments.output import _compute_ylimits_for_featureset
  from skll.learner import Learner
  from skll.utils.constants import VALID_TASKS
  from skll.utils.logging import close_and_remove_logger_handlers, get_skll_logger
  from skll.utils.testing import backward_compatibility_dir, config_dir, create_jsonlines_feature_files, fill_in_config_options, fill_in_config_paths, fill_in_config_paths_for_single_file, make_classification_data, make_digits_data, make_regression_data, other_dir, output_dir, remove_jsonlines_feature_files, test_dir, tests_dir, train_dir, unlink
label_desc: Use image node_id 20 for calling the TestOutput obj's underlying member method code with example usage: obj.test_learning_curve_min_examples_check() without return types