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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 weather(api_key, latitude, longitude, date_time=None):
 # type:(str, float, float) -> Weather """ This is a shortcut method that can be used to perform a basic weather request with the default settings. :param str api_key: Darksky.net API key :param float latitude: The requested latitude. Maybe different from the value returned from an API request :param float longitude: The requested longitude. Maybe different from the value returned from an API request :param date_time: The requested date/time. :rtype: Weather """

    return DarkSky(api_key).weather(latitude, longitude, date_time)