code: def test_indicators_filter_variables(df_vartypes):
      transformer = Winsorizer(
          variables=["Age", "Marks"],
          tail="both",
          capping_method="quantiles",
          fold=0.1,
          add_indicators=True,
      )
      X = transformer.fit_transform(df_vartypes)
      assert X.shape[1] == df_vartypes.shape[1] + 4
  
      transformer.set_params(tail="left")
      X = transformer.fit_transform(df_vartypes)
      assert X.shape[1] == df_vartypes.shape[1] + 2
  
      transformer.set_params(tail="right")
      X = transformer.fit_transform(df_vartypes)
      assert X.shape[1] == df_vartypes.shape[1] + 2
  
imports: import math
  import numpy
  import pandas
  import pytest
  from feature_engine.outliers import Winsorizer
label_desc: Use image node_id 12 for calling a global function with example usage: test_indicators_filter_variables(df_vartypes) without return types