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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 add_weatherdata(self, data):
 """Appends weather data. Args: data (WeatherData):
 weather data object """

        if not isinstance(data, WeatherData):
            raise ValueError('Weather data need to be of type WeatherData')
        self._data["WEATHER DATA"].append(data)