Returns a Series mapping each holiday (as a UTC midnight Timestamp)
    in ``calendar`` between ``start`` and ``end`` to that session at
    ``time`` (as a UTC Timestamp).

def scheduled_special_times(calendar, start, end, time, tz):
    """
    Returns a Series mapping each holiday (as a UTC midnight Timestamp)
    in ``calendar`` between ``start`` and ``end`` to that session at
    ``time`` (as a UTC Timestamp).
    """
    days = calendar.holidays(start, end)
    return pd.Series(
        index=pd.DatetimeIndex(days, tz=UTC),
        data=days_at_time(days, time, tz=tz),
    )