code: def isholiday(self, date):
          
          date = parsefun(date)
          if self.holidays:
              # i is the index of first holiday >= date
              i = bisect.bisect_left(self.holidays, date)
              if i == 0 and date < self.holidays[0]:
                  warn('Holiday list exhausted at start, ' \
                       'isholiday(%s) output may be incorrect.' % date)
              elif i == len(self.holidays):
                  warn('Holiday list exhausted at end, ' \
                       'isholiday(%s) output may be incorrect.' % date)
              elif self.holidays[i] == date:
                  return True
          return False
docs: Check if a given date is a holiday.
  
          Args:
              date (date, datetime or str): Date to be checked.
  
          Returns:
              bool: True if the date is a holiday, False otherwise.