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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 get_percentiles(self, field=None, percents=None):
 """ Create a percentile aggregation object and add it to the aggregation dict :param field: the field present in the index that is to be aggregated :param percents: the specific percentiles to be calculated default: [1.0, 5.0, 25.0, 50.0, 75.0, 95.0, 99.0] :returns: self, which allows the method to be chainable with the other methods """


        if not field:
            raise AttributeError("Please provide field to apply aggregation to!")
        if not percents:
            percents = [1.0, 5.0, 25.0, 50.0, 75.0, 95.0, 99.0]
        agg = A("percentiles", field=field, percents=percents)

        self.aggregations['percentiles_' + field] = agg
        return self