code: def test_include(self):
      df = pd.DataFrame(
          {"a": [1, 2, 3, 4], "b": [2, 3, 4, 5], "c": [3, 4, 5, 6]}
      )
      ds = ray.data.from_pandas(df)
      prep = Concatenator(include=["a", "b"])
      new_ds = prep.transform(ds)
      for _, row in enumerate(new_ds.take()):
          assert set(row) == {"concat_out", "c"}
  
file_path: ray/python/ray/data/tests/preprocessors/test_concatenator.py
imports: import numpy
  import pandas
  import pytest
  import ray
  from ray.data.preprocessors import Concatenator
label_desc: Use image node_id 4 for calling the TestConcatenator obj's underlying member method code with example usage: obj.test_include() without return types