code: def default_holidays():
      """Default holidays by country params"""
      start_year = 2015
      end_year = 2030
      holiday_pre_num_days = [2]
      holiday_post_num_days = [2]
      expected_holidays = ProphetTemplate().get_prophet_holidays(
          year_list=list(
              range(start_year - 1, end_year + 2)
          ),  # covers one more year on both sides.
          countries="auto",
          lower_window=-holiday_pre_num_days[0],
          upper_window=holiday_post_num_days[0],
      )
      return expected_holidays
  
imports: import datetime
  import sys
  import warnings
  import numpy
  import pandas
  import pytest
  from pandas.testing import assert_frame_equal
  import greykite.common.constants
  from greykite.common.evaluation import EvaluationMetricEnum
  from greykite.common.python_utils import assert_equal
  from greykite.common.testing_utils import generate_df_for_tests
  from greykite.common.testing_utils import generate_df_with_reg_for_tests
  from greykite.framework.constants import COMPUTATION_N_JOBS
  from greykite.framework.constants import CV_REPORT_METRICS_ALL
  from greykite.framework.templates.autogen.forecast_config import ComputationParam
  from greykite.framework.templates.autogen.forecast_config import EvaluationMetricParam
  from greykite.framework.templates.autogen.forecast_config import EvaluationPeriodParam
  from greykite.framework.templates.autogen.forecast_config import ForecastConfig
  from greykite.framework.templates.autogen.forecast_config import MetadataParam
  from greykite.framework.templates.autogen.forecast_config import ModelComponentsParam
  from greykite.framework.templates.forecaster import Forecaster
  from greykite.framework.templates.model_templates import ModelTemplateEnum
  from greykite.framework.templates.prophet_template import ProphetTemplate
  from greykite.framework.utils.framework_testing_utils import assert_basic_pipeline_equal
  from greykite.sklearn.estimator.prophet_estimator import ProphetEstimator
label_desc: Use image node_id 1 for calling a global function with example usage: default_holidays() and returns: expected_holidays