code: def test_holidays(holiday):
      for test_date in test_dates[holiday]:
          test_date = pd.to_datetime(test_date)
          distance_function = SPECIAL_DATE_FEATURES[holiday]
          assert (
              distance_function(test_date) == 0
          ), "The supplied date should be {} but is not!".format(
              holiday
          )
  
imports: import numpy
  import pandas
  import pytest
  from gluonts.time_feature.holiday import BLACK_FRIDAY, CHRISTMAS_DAY, CHRISTMAS_EVE, COLUMBUS_DAY, CYBER_MONDAY, EASTER_MONDAY, EASTER_SUNDAY, GOOD_FRIDAY, INDEPENDENCE_DAY, LABOR_DAY, MARTIN_LUTHER_KING_DAY, MEMORIAL_DAY, MOTHERS_DAY, NEW_YEARS_DAY, NEW_YEARS_EVE, PRESIDENTS_DAY, SPECIAL_DATE_FEATURES, SUPERBOWL, THANKSGIVING, SpecialDateFeatureSet, squared_exponential_kernel
label_desc: Use image node_id 1 for calling a global function with example usage: test_holidays(holiday) without return types