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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def sunset(self, date=None, zenith=None):
 """Calculate sunset times for locations. Args: date (datetime.date):
 Calculate rise or set for given date zenith (str):
 Calculate sunset events, or start of twilight times Returns: list of list of datetime.datetime: The time for the sunset for each point in each segment """

        return (segment.sunset(date, zenith) for segment in self)