code: def test_create_regressor_for_future_dates():
      # create inputs
      input_df_regressor = pd.DataFrame(
          {
              "ts": pd.date_range(
                  datetime(2020, 1, 1), freq="D", periods=30
              ),
              "actual": [100] * 10 + [200] * 10 + [300] * 10,
              f"{LEVELSHIFT_COL_PREFIX_SHORT}_2020_01_11_00_00": [0]
              * 10
              + [1] * 20,
              f"{LEVELSHIFT_COL_PREFIX_SHORT}_2020_01_21_00_00": [0]
              * 20
              + [1] * 10,
          }
      )
  
      # create expected outputs
      expected_df = pd.DataFrame(
          {
              "ts": pd.date_range(
                  datetime(2020, 1, 1), freq="D", periods=35
              ),
              "actual": [100] * 10
              + [200] * 10
              + [300] * 10
              + [None] * 5,
              f"{LEVELSHIFT_COL_PREFIX_SHORT}_2020_01_11_00_00": [0]
              * 10
              + [1] * 25,
              f"{LEVELSHIFT_COL_PREFIX_SHORT}_2020_01_21_00_00": [0]
              * 20
              + [1] * 15,
          }
      )
  
      # call the function
      detector = ShiftDetection()
      (
          output_regressor_col,
          output_df,
      ) = detector.create_regressor_for_future_dates(
          input_df_regressor,
          time_col="ts",
          value_col="actual",
          forecast_horizon=5,
          freq="D",
      )
  
      # unit test
      pd.testing.assert_frame_equal(output_df, expected_df)
      assert output_regressor_col == [
          f"{LEVELSHIFT_COL_PREFIX_SHORT}_2020_01_11_00_00",
          f"{LEVELSHIFT_COL_PREFIX_SHORT}_2020_01_21_00_00",
      ]
  
file_path: greykite/greykite/tests/algo/changepoint/shift_detection/test_shift_detector.py
imports: from datetime import datetime
  import pandas
  import pytest
  from greykite.algo.changepoint.shift_detection.shift_detector import ShiftDetection
  from greykite.common.constants import LEVELSHIFT_COL_PREFIX_SHORT
label_desc: Use image node_id 7 for calling a global function with example usage: test_create_regressor_for_future_dates() without return types