code: def data():
      """Generates dataset for test cases
      :return: pd.DataFrame with columns of type:
          datetime, number, number, boolean, object, category
      """
      df = generate_df_with_reg_for_tests(
          freq="D", periods=50, remove_extra_cols=False
      )["df"]
      df["dow_categorical"] = df["str_dow"].astype("category")
      df = df[
          [
              TIME_COL,
              "regressor1",
              "regressor2",
              "regressor_bool",
              "str_dow",
              "dow_categorical",
          ]
      ]
      return df
  
file_path: greykite/greykite/tests/sklearn/transform/test_dtype_column_selector.py
imports: import pytest
  from greykite.common.constants import TIME_COL
  from greykite.common.testing_utils import generate_df_with_reg_for_tests
  from greykite.sklearn.transform.dtype_column_selector import DtypeColumnSelector
label_desc: Use image node_id 1 for calling a global function with example usage: data() and returns: df