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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 _extract_number_of_taxa(self):
 """ sets `self.number_taxa` to the number of taxa as string """

        n_taxa = dict()
        for i in self.seq_records:
            if i.gene_code not in n_taxa:
                n_taxa[i.gene_code] = 0
            n_taxa[i.gene_code] += 1
        number_taxa = sorted([i for i in n_taxa.values()], reverse=True)[0]
        self.number_taxa = str(number_taxa)