code: def test_scale_transformation():
      """[Utils] Scale: check transformation."""
      g = np.array([[-2.0, -4.0], [0.0, 0.0], [2.0, 4.0]])
  
      x = np.arange(6).reshape(3, 2)
      x[:, 1] *= 2
      s = Scale().fit_transform(x)
  
      np.testing.assert_array_equal(s, g)
  
imports: import numpy
  import os
  from mlens.ensemble.base import Layer, Sequential
  from mlens.utils.dummy import OLS, LogisticRegression, Scale
  from mlens.testing.dummy import ESTIMATORS, PREPROCESSING, ESTIMATORS_PROBA, ECM, ECM_PROBA, InitMixin
  from mlens.testing.dummy import Data, EstimatorContainer
  from mlens.utils import assert_correct_format
  from mlens.utils.formatting import _assert_format, _format_instances
  from mlens.utils.exceptions import NotFittedError
  from mlens.externals.sklearn.base import BaseEstimator
label_desc: Use image node_id 11 for calling a global function with example usage: test_scale_transformation() without return types