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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_select(self, *column):
 """ Add a new select column to query :param column: The column to add :type column: str :return: The current QueryBuilder instance :rtype: QueryBuilder """

        if not column:
            column = []

        self.columns += list(column)

        return self