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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 interaction_columns_used(self):
 """ Columns from the interaction dataset used for filtering and in the model. These may come originally from either the choosers or alternatives tables. """

        return list(tz.unique(tz.concatv(
            util.columns_in_filters(self.interaction_predict_filters),
            util.columns_in_formula(self.model_expression))))