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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_gene(self, gene_name):
 """Get a gene from the cache or attempt to disambiguate or add a new record. """

        if not gene_name:
            return

        gene_pk = self.genes.get(gene_name)
        if gene_pk:
            return gene_pk

        chrom = self.chromosomes[self.variants.chrom]
        gene = Gene.objects.find(gene_name, chrom, create=True)
        if gene:
            return gene.pk