code: def daily_data():
      return generate_df_for_tests(
          freq="D",
          periods=730,
          train_start_date=datetime.datetime(2018, 1, 1),
          conti_year_origin=2018,
      )
  
file_path: greykite/greykite/tests/sklearn/estimator/test_one_by_one_estimator.py
imports: import datetime
  import sys
  import pandas
  import pytest
  from sklearn.metrics import mean_squared_error
  import greykite.common.constants
  from greykite.common.testing_utils import generate_df_for_tests
  from greykite.sklearn.estimator.one_by_one_estimator import OneByOneEstimator
  from greykite.sklearn.estimator.simple_silverkite_estimator import SimpleSilverkiteEstimator
label_desc: Use image node_id 1 for calling a global function with example usage: daily_data() and returns: generate_df_for_tests