<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def sun_events(latitude, longitude, date, timezone=0, zenith=None):
 """Convenience function for calculating sunrise and sunset. Civil twilight starts/ends when the Sun's centre is 6 degrees below the horizon. Nautical twilight starts/ends when the Sun's centre is 12 degrees below the horizon. Astronomical twilight starts/ends when the Sun's centre is 18 degrees below the horizon. Args: latitude (float):
 Location's latitude longitude (float):
 Location's longitude date (datetime.date):
 Calculate rise or set for given date timezone (int):
 Offset from UTC in minutes zenith (str):
 Calculate rise/set events, or twilight times Returns: tuple of datetime.time: The time for the given events in the specified timezone """

    return (sun_rise_set(latitude, longitude, date, 'rise', timezone, zenith),
            sun_rise_set(latitude, longitude, date, 'set', timezone, zenith))