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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 build_model_from_txt(self, fname):
 """ Construct the model and perform regressions based on data in a txt file. Parameters fname : str The name of the file to load. """

        x_values, y_values = read_column_data_from_txt(fname)
        self.build_model_from_xy(x_values, y_values)