code: def test_boxcox_transform(self):
      log_mapper = Mapper(lambda x: np.log(x))
      boxcox = BoxCox(lmbda=0)
  
      transformed1 = log_mapper.transform(self.sine_series)
      transformed2 = boxcox.fit(self.sine_series).transform(
          self.sine_series
      )
  
      np.testing.assert_almost_equal(
          transformed1.all_values(copy=False),
          transformed2.all_values(copy=False),
          decimal=4,
      )
  
file_path: darts/darts/tests/dataprocessing/transformers/test_boxcox.py
imports: from copy import deepcopy
  import numpy
  import pandas
  import pytest
  from darts import TimeSeries
  from darts.dataprocessing.transformers import BoxCox, Mapper
  from darts.utils.timeseries_generation import linear_timeseries, sine_timeseries
label_desc: Use image node_id 2 for calling the TestBoxCox obj's underlying member method code with example usage: obj.test_boxcox_transform() without return types