new_contents: import logging
  from datetime import datetime
  
  from workalendar.europe import France, Luxembourg
  from workalendar.usa import California
  from workalendar.asia import Taiwan
  
  log = logging.getLogger(__file__)
  
  conv_table = {
      'fr': France,
      'us': California,
      'zh': Taiwan,
      'lu': Luxembourg,
  }
  
  
  def get_holiday(user, year=None, use_datetime=False):
      """ return holidays for user country
  
      format is unixtime for javascript
      """
      klass = conv_table[user.country]
  
      cal = klass()
      current_year = year or datetime.now().year
      # must cast to datetime as workalendar returns only Date objects
      holiday_current = [datetime(dt.year, dt.month, dt.day)
                         for dt, _ in cal.holidays(current_year)]
      if not use_datetime:
          holiday_current = [int(dt.strftime("%s")) * 1000
                             for dt in holiday_current]
  
      next_year = current_year + 1
      holiday_next = [datetime(dt.year, dt.month, dt.day)
                      for dt, _ in cal.holidays(next_year)]
      if not use_datetime:
          holiday_next = [int(dt.strftime("%s")) * 1000
                          for dt in holiday_next]
  
      return holiday_current + holiday_next
  
subject: Add helper method to retrieve holidays list