human
Here's a good function header given the following:
I wrote the below code

    (MIN_YEAR, MAX_YEAR) = (Timestamp.min.year, Timestamp.max.year)
    MAX_DAY_DELTA = (Timestamp.max - datetime.datetime(1960, 1, 1)).days
    MIN_DAY_DELTA = (Timestamp.min - datetime.datetime(1960, 1, 1)).days
    MIN_MS_DELTA = (((MIN_DAY_DELTA * 24) * 3600) * 1000)
    MAX_MS_DELTA = (((MAX_DAY_DELTA * 24) * 3600) * 1000)
    def convert_year_month_safe(year, month):
        '\n                                Convert    year    and    month    to    datetimes,    using    pandas    vectorized    versions\n                                when    the    date    range    falls    within    the    range    supported    by    pandas.        Other\n                                wise    it    falls    back    to    a    slower    but    more    robust    method    using    datetime.\n                                '
        if ((year.max() < MAX_YEAR) and (year.min() > MIN_YEAR)):
            return to_datetime(((100 * year) + month), format='%Y%m')
        else:
            index = getattr(year, 'index', None)
            return Series([datetime.datetime(y, m, 1) for (y, m) in zip(year, month)], index=index)
    def convert_year_days_safe(year, days):
        '\n                                Converts    year    (e.g.    1999)    and    days    since    the    start    of    the    year    to    a\n                                datetime    or    datetime64    Series\n                                '
        if ((year.max() < (MAX_YEAR - 1)) and (year.min() > MIN_YEAR)):
            return (to_datetime(year, format='%Y') + to_timedelta(days, unit='d'))
        else:
            index = getattr(year, 'index', None)
            value = [(datetime.datetime(y, 1, 1) + relativedelta(days=int(d))) for (y, d) in zip(year, days)]
            return Series(value, index=index)
    def convert_delta_safe(base, deltas, unit):
        '\n                                Convert    base    dates    and    deltas    to    datetimes,    using    pandas    vectorized\n                                versions    if    the...

What's a good function header?
assistant
#Here's a good function header.

def _stata_elapsed_date_to_datetime_vec(dates, fmt):