code: def test_get_feature_names():
      df = pd.DataFrame({"a": [4, 5, 6], "b": ["4", "5", "6"]})
      transformer = ColumnDropper("a").fit(df)
      assert transformer.get_feature_names() == ["b"]
  
file_path: scikit-lego/tests/test_preprocessing/test_columndropper.py
imports: import pandas
  import pytest
  from pandas.testing import assert_frame_equal
  from sklearn.pipeline import make_pipeline
  from sklego.preprocessing import ColumnDropper
label_desc: Use image node_id 8 for calling a global function with example usage: test_get_feature_names() without return types