import datetime
import calendar

def day_in_1970_from_month_and_week(month, week):
    if month < 1 or month > 12 or week < 1 or week > 5:
        raise ValueError("invalid time: month=%d, week=%d" % (month, week))

    oneday = datetime.timedelta(days=1)
    oneweek = datetime.timedelta(days=7)

    first_sunday = datetime.date(1970, month, 1)
    while first_sunday.weekday() != calendar.SUNDAY:
        first_sunday += oneday

    while True:
        day = first_sunday + (oneweek * (week - 1))
        if day.month != month:
            week -= 1
        else:
            break

    return day.day

def format_tz_time_string(month, week, hour):
    day = day_in_1970_from_month_and_week(month, week)
    return "1970%02i%02iT%02i0000" % (month, day, hour)