def get_num_missed_windows(case):
    domain_obj = Domain.get_by_name(case.domain, strict=True)
    # unlike in most other projects, case.opened_on is actually in UTC
    # because it was submitted from cloudcare
    opened_timestamp = (PhoneTime(case.opened_on, pytz.UTC)
                        .user_time(domain_obj.get_default_timezone()).done())
    day_of_week = opened_timestamp.weekday()
    time_of_day = opened_timestamp.time()

    # In order to use timedelta, we need a datetime
    current_time = datetime.combine(date(2000, 1, 1), time_of_day)
    window_time = datetime.combine(date(2000, 1, 1), WINDOWS[day_of_week][0])

    if current_time < window_time:
        return 0

    window_interval = (WINDOWS[day_of_week][1] - 60) / 5
    for i in range(1, 5):
        window_time += timedelta(minutes=window_interval)
        if current_time < window_time:
            return i

    return 5
Get the number of reminder events that were missed on registration day.
dataset/ETHPy150Open dimagi/commcare-hq/custom/fri/api.py/get_num_missed_windows