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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 abundances(self, ids=None):
 """ Query the results table to get abundance data for all or some tax ids """

        # TODO: Consider removing this method... since it's kind of trivial
        #       May want to replace with something that actually gets genome-size adjusted
        #       abundances from the results table
        if ids is None:
            # get the data frame
            return self.table()

        else:
            res = self.table()
            return res[res["tax_id"].isin(ids)]