How works a thermostat?
    Thermostat is a device which controlls temperature.
    
How temperature is controlled by thermostat?
    Thermostat sets the temperature according to the time.
    
What is the thermostat interface?
    You can set temperature using thermostat_setting by entering proper number of degrees. Thermostat_setting may vary on different time.
    Time is represented by date, hour or office operations. You can specify also year seasons as a time periods for which you may set different temperature.
    Also you may specify which days of week are workdays or weekend.
    Date is properly month and day of this month. Months are: January, February, March, April, May, June, July, August, September, October, Novomber and December.
    Seasons are: summer, autumn, winter and spring.
    
What are the default settings of thermostat?
    By default thermostat_settings are:
    In spring for operations during bussines hours thermostat_setting is 20 degrees for operations not during bussines hours thermostat_setting is 15 degrees.
    In summer for operations during bussines hours thermostat_setting is 24 degrees for operations not during  bussines hours thermostat_setting is 27 degrees.
    In autumn for operations during bussines hours thermostat_setting is 20 degrees for operations not during  bussines hours thermostat_setting is 16 degrees.
    In winter for operations during bussines hours thermostat_setting is 18 degrees for operations not during  bussines hours thermostat_setting is 14 degrees.
    
    Operations during  bussines hours are on workdays for time between 9 am and 5 pm. Before 9 am and after 5 pm on workdays and throughout weekend operations are not during bussiness hours.
    Workdays are: Monday, Tuesday, Wednesday, Thursday and Friday. It is weekend if today is Saturday or Sunday.
        
    Months are divided into seasons as follows:
        January, February and December correspond to the summer, 
        March, April and May correspond to the autumn,
        June, July and August correspond to the winter, 
        September, October and November correspond to the spring.