Newbie question to find the seconds between now and midnight

[ODIS]

Here is a quick OOP example of your market opening hours checking:

from datetime import datetime, time
import time as time_time


class MarketOpeningHours:
    """Representation of market opening hours (e.g. 13:00 - 14:00)"""

    def __init__(self, opening_time: time, closing_time: time):
        if closing_time <= opening_time:
            raise Exception("Closing time must be later than opening time!")
        self.opening_time = opening_time
        self.closing_time = closing_time

    def is_open(self) -> bool:
        return self.opening_time <= datetime.now().time() <= self.closing_time


class Market:
    """Representation of market"""

    def __init__(self):
        self.opening_hours_list = []

    def add_opening_hours(self, opening_hours: MarketOpeningHours):
        self.opening_hours_list.append(opening_hours)

    def is_open(self) -> bool:
        for opening_hours in self.opening_hours_list:
            if opening_hours.is_open():
                return True
        return False


class MarketsList:
    """Representation of markets list"""

    def __init__(self):
        self.markets = []

    def add_market(self, market: Market):
        self.markets.append(market)

    def is_any_market_open(self) -> bool:
        for market in self.markets:
            if market.is_open():
                return True
        return False


market_a = Market()
market_a.add_opening_hours(MarketOpeningHours(time(9, 0), time(11, 0)))
market_a.add_opening_hours(MarketOpeningHours(time(13, 0), time(15, 0)))

market_b = Market()
market_b.add_opening_hours(MarketOpeningHours(time(9, 0), time(11, 0)))
market_b.add_opening_hours(MarketOpeningHours(time(13, 0), time(15, 15)))

market_c = Market()
market_c.add_opening_hours(MarketOpeningHours(time(9, 0), time(10, 30)))
market_c.add_opening_hours(MarketOpeningHours(time(11, 0), time(13, 0)))
market_c.add_opening_hours(MarketOpeningHours(time(14, 0), time(15, 0)))

markets_list = MarketsList()
markets_list.add_market(market_a)
markets_list.add_market(market_b)
markets_list.add_market(market_c)

while markets_list.is_any_market_open():
    print(str(datetime.now().time()) + ": some market is still open - waiting")
    time_time.sleep(1)