Add a new select column to query

        :param column: The column to add
        :type column: str

        :return: The current QueryBuilder instance
        :rtype: QueryBuilder

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