class_docstr: Tests that data transformers inheriting from `FittableDataTransformer` class behave
  correctly when `global_fit` attribute is `False`.
docstr: Tests for correct transformation of single series.
code: def test_input_transformed_single_series(self):
      """
      Tests for correct transformation of single series.
      """
      test_input = constant_timeseries(value=1, length=10)
  
      mock = self.DataTransformerMock(scale=2, translation=10)
  
      transformed = mock.fit_transform(test_input)
  
      # 2 * 1 + 10 = 12
      expected = constant_timeseries(value=12, length=10)
      assert transformed == expected
  
file_path: darts/darts/tests/dataprocessing/transformers/test_fittable_data_transformer.py
imports: from typing import Any, Mapping, Sequence, Union
  import numpy
  from darts import TimeSeries
  from darts.dataprocessing.transformers.fittable_data_transformer import FittableDataTransformer
  from darts.utils.timeseries_generation import constant_timeseries
label_desc: Use image node_id 1 for calling the TestLocalFittableDataTransformer obj's underlying member method code with example usage: obj.test_input_transformed_single_series() without return types