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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 prepare(self, dataframe):
 """ Takes the already cleaned dataframe, splits it into train and test and returns the train and test as numpy arrays. If the problem is supervised, the target column will be that last one of the returned arrays. """

        mapping = DataFrameMapCreator().get_mapping_from_config(self.__config)
        self.__mapper = DataFrameMapper(mapping)
        train, test = split_dataframe_train_test(dataframe, self.__config.get_option_parameter("split", "train_percentage"))
        return self.__get_correct_return_parameters(train, test)