为什么Pythonw文件占用大量CPU资源？

Question

我编写了一个.pyw文件，并在后台运行它。但是，当我什么都不做时，它需要29％的CPU。如果我启动任何其他软件，它将开始占用49％-50％的CPU。有什么方法可以减少CPU使用率？

代码：

def check():
    time = str(datetime.datetime.now())
    time = time[11:13] + time[14:16]
    today = str(datetime.datetime.today())
    today = today[:4] + today[5:7] + today[8:10]
    
    file = open("alarms\\Today\\today.txt", "r")
    alarms = file.readlines()
    file.close()
    
    ID = ""
    hasAlarm = False
    i = 0
    while i < len(alarms):
        if time in alarms[i]:
            hasAlarm = True
            ID = alarms[i+1]
            break
        i += 2
    
    if hasAlarm:
        file = open("alarms\\ID\\alarmID.txt", "r")
        alarms = file.readlines()
        file.close()
        i = 0
        while i < len(alarms):
            if ID in alarms[i]:
                break
            i += 6
        name = alarms[i+1][:-1]
        showtime = change24to12(alarms[i+2][:-1])
        if os.path.exists(alarms[i+5][:-1]):
            ringtone = alarms[i+5][:-1]
        else:
            ringtone = "basic.mp3"
        
        app = QApplication(sys.argv)
        window = AlarmWindow(name, showtime, ringtone)

        file = open("alarms\\Today\\today.txt", "r")
        alarms = file.readlines()
        file.close()
        file = open("alarms\\Today\\today.txt", "w")
        file.writelines(alarms[2:])
        file.close()
        
        file = open("alarms\\Special Days\\" + today + ".txt", "r")
        alarms = file.readlines()
        file.close()
        i = 0
        flag = False
        while i < len(alarms):
            if time in alarms[i]:
                flag = True
                break
            i += 2
        if flag:
            file = open("alarms\\Special Days\\" + today + ".txt", "w")
            file.writelines(alarms[:i] + alarms[i+2:])
            file.close()

        notification.notify(title=name, message=showtime)

        app.exec()
while True:
    check()

我希望无限循环运行并从后台调用函数。