def holiday?(date)
      trade_cals = trade_cal
      holidays = trade_cals.select { |object| object['is_open'] == 0 }
                           .map { |object| object['date'] }
      [6, 7].include?(date.cwday) ||
        holidays.include?(date.strftime('%F'))
    end
def holiday?(date)
      trade_cals = trade_cal
      holidays = trade_cals.select { |object| object['is_open'] == 0 }
                           .map { |object| object['date'] }
      [6, 7].include?(date.cwday) ||
        holidays.include?(date.strftime('%F'))
    end
判断是否为交易日，返回 true or false