code: def test_duplicate_index_value(self):
      for encoder_name in encoders.__all__:
          with self.subTest(encoder_name=encoder_name):
              enc = getattr(encoders, encoder_name)(cols=["x"])
              data = pd.DataFrame(
                  {
                      "x": ["a", "b", "c", "d", "e"],
                      "y": [1, 0, 1, 0, 1],
                  },
                  index=[1, 2, 2, 3, 4],
              )
              result = enc.fit_transform(data[["x"]], data["y"])
              self.assertEqual(5, len(result))
  
imports: import warnings
  from datetime import timedelta
  import numpy
  from numpy.testing import assert_array_equal
  import pandas
  import sklearn
  import tests.helpers
  from sklearn.utils.estimator_checks import check_transformer_general, check_transformers_unfitted, check_n_features_in
  from sklearn.compose import ColumnTransformer
  from unittest import TestCase
  from copy import deepcopy
  import category_encoders
label_desc: Use image node_id 27 for calling the TestEncoders obj's underlying member method code with example usage: obj.test_duplicate_index_value() without return types