code: def fit_transform(
      self, data_inputs, expected_outputs=None
  ) -> Tuple["BaseStep", Any]:
      self._add_fitted_data(data_inputs, expected_outputs)
      return self, self.transform(data_inputs)
  
imports: import copy
  from typing import Any, Tuple
  import numpy
  import pytest
  from neuraxle.base import BaseStep
  from neuraxle.steps.column_transformer import ColumnTransformer
label_desc: Use image node_id 3 for calling the MultiplyBy2 obj's underlying member method code with example usage: obj.fit_transform(data_inputs, expected_outputs) and returns: self,  self