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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 order_by(self, column, direction="asc"):
 """ Add a "order by" clause to the query :param column: The order by column :type column: str :param direction: The direction of the order :type direction: str :return: The current QueryBuilder instance :rtype: QueryBuilder """

        if self.unions:
            prop = "union_orders"
        else:
            prop = "orders"

        if direction.lower() == "asc":
            direction = "asc"
        else:
            direction = "desc"

        getattr(self, prop).append({"column": column, "direction": direction})

        return self