main.py

from datetime import datetime
from collections import OrderedDict


def generate_sid():
    current_sid = 1
    while True:
        yield str(current_sid)
        current_sid += 1


class SessionManager:
    __sid_generator = generate_sid()
    __sessions = OrderedDict()

    def createSession(self, id):
        sid = next(self.__sid_generator)
        current_time = datetime.now()
        self.__sessions[sid] = (id, current_time)
        return sid

    def checkSession(self, sid: str):
        session = self.__sessions.get(sid)
        if session:
            id, previous_time = session
            current_time = datetime.now()
            time_delta = current_time - previous_time
            if time_delta.seconds > 600:
                del self.__sessions[sid]
                return None
            else:
                self.__sessions[sid] = (id, current_time)
                return id
        else:
            return None

    def cleanup(self):
        current_time = datetime.now()
        if len(self.__sessions) == 0:
            return
        while len(self.__sessions) > 0:
            sid, (id, previous_time) = self.__sessions.popitem()
            if (current_time - previous_time).seconds < 601:
                self.__sessions[sid] = id, previous_time
                break