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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 find(self, id, columns=None):
 """ Execute a query for a single record by id :param id: The id of the record to retrieve :type id: mixed :param columns: The columns of the record to retrive :type columns: list :return: mixed :rtype: mixed """

        if not columns:
            columns = ['*']

        return self.where('id', '=', id).first(1, columns)