message: Update sklearn imports for deprecated packages.
diff: @@ -194,7 +194,7 @@ if TRY_IMPORT_SKLEARN:
  # pylint: disable=g-import-not-at-top,g-multiple-import,unused-import
  from sklearn.base import BaseEstimator, ClassifierMixin, RegressorMixin, TransformerMixin
  from sklearn.metrics import accuracy_score, log_loss, mean_squared_error
  - from sklearn.cross_validation import train_test_split
  + from sklearn.model_selection import train_test_split
  try:
  from sklearn.exceptions import NotFittedError
  except ImportError:
  