code: def test_guerrero_against_r_implementation(bounds, r_lambda):
      """Test BoxCoxTransformer against forecast guerrero method.
  
      Testing lambda values estimated by the R implementation of the Guerrero method
      https://github.com/robjhyndman/forecast/blob/master/R/guerrero.R
      against the guerrero method in BoxCoxTransformer.
      R code to generate the hardcoded value for bounds=(-1, 2) used in the test
      ('Airline.csv' contains the data from 'load_airline()'):
          airline_file <- read.csv(file = 'Airline.csv')[,c('Passengers')]
          airline.ts <- ts(airline_file)
          guerrero(airline.ts, lower=-1, upper=2, nonseasonal.length = 20)
      Output:
          -0.156981228426408
      """
      y = load_airline()
      t = BoxCoxTransformer(bounds=bounds, method="guerrero", sp=20)
      t.fit(y)
      np.testing.assert_almost_equal(t.lambda_, r_lambda, decimal=4)
  
imports: import numpy
  import pytest
  from sktime.datasets import load_airline
  from sktime.transformations.series.boxcox import BoxCoxTransformer
  from sktime.utils.validation._dependencies import _check_soft_dependencies
label_desc: Use image node_id 3 for calling a global function with example usage: test_guerrero_against_r_implementation(bounds, r_lambda) without return types