code: def test_indent():
      """Assert that indenting a multiline string by 4 spaces prepends 4 spaces before each new line."""
      multiline_string = """test
  test1
  test2
  test3"""
  
      indented_multiline_string = """    test
      test1
      test2
      test3"""
  
      assert indented_multiline_string == _indent(multiline_string, 4)
  
imports: from tqdm import tqdm
  import numpy
  from os import remove, path
  from tpot import TPOTClassifier, TPOTRegressor
  from tpot.export_utils import export_pipeline, generate_import_code, _indent, generate_pipeline_code, get_by_name, set_param_recursive
  from tpot.operator_utils import TPOTOperatorClassFactory
  from tpot.config.classifier import classifier_config_dict
  from sklearn.datasets import load_digits
  from sklearn.model_selection import train_test_split
  from deap import creator
  from nose.tools import assert_raises, assert_equal, nottest
label_desc: Use image node_id 21 for calling a global function with example usage: test_indent() without return types