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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 _process_kegg_disease2gene(self, limit=None):
 """ This method creates an association between diseases and their associated genes. We are being conservative here, and only processing those diseases for which there is no mapping to OMIM. Triples created: <alternate_locus> is an Individual <alternate_locus> has type <variant_locus> <alternate_locus> is an allele of <gene_id> <assoc_id> has subject <disease_id> <assoc_id> has object <gene_id> :param limit: :return: """


        LOG.info("Processing KEGG disease to gene")
        if self.test_mode:
            graph = self.testgraph
        else:
            graph = self.graph
        model = Model(graph)
        line_counter = 0
        geno = Genotype(graph)
        rel = self.globaltt['is marker for']
        noomimset = set()
        raw = '/'.join((self.rawdir, self.files['disease_gene']['file']))
        with open(raw, 'r', encoding="iso-8859-1") as csvfile:
            filereader = csv.reader(csvfile, delimiter='\t', quotechar='\"')
            for row in filereader:
                line_counter += 1
                (gene_id, disease_id) = row

                if self.test_mode and gene_id not in self.test_ids['genes']:
                    continue

                gene_id = 'KEGG-' + gene_id.strip()
                disease_id = 'KEGG-' + disease_id.strip()

                # only add diseases for which
                # there is no omim id and not a grouping class
                if disease_id not in self.kegg_disease_hash:
                    # add as a class
                    disease_label = None
                    if disease_id in self.label_hash:
                        disease_label = self.label_hash[disease_id]
                    if re.search(r'includ', str(disease_label)):
                        # they use 'including' when it's a grouping class
                        LOG.info(
                            "Skipping this association because " +
                            "it's a grouping class: %s",
                            disease_label)
                        continue
                    # type this disease_id as a disease
                    model.addClassToGraph(disease_id, disease_label)
                    # , class_type=self.globaltt['disease'])
                    noomimset.add(disease_id)
                    alt_locus_id = self._make_variant_locus_id(gene_id, disease_id)
                    alt_label = self.label_hash[alt_locus_id]
                    model.addIndividualToGraph(
                        alt_locus_id, alt_label, self.globaltt['variant_locus'])
                    geno.addAffectedLocus(alt_locus_id, gene_id)
                    model.addBlankNodeAnnotation(alt_locus_id)
                    # Add the disease to gene relationship.
                    assoc = G2PAssoc(graph, self.name, alt_locus_id, disease_id, rel)
                    assoc.add_association_to_graph()

                if not self.test_mode and (
                        limit is not None and line_counter > limit):
                    break

        LOG.info("Done with KEGG disease to gene")
        LOG.info("Found %d diseases with no omim id", len(noomimset))

        return