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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_stock_genotype(self, limit):
 """ The genotypes of the stocks. :param limit: :return: """


        if self.test_mode:
            graph = self.testgraph
        else:
            graph = self.graph

        raw = '/'.join((self.rawdir, 'stock_genotype'))
        LOG.info("processing stock genotype")
        line_counter = 0

        with open(raw, 'r') as f:
            filereader = csv.reader(f, delimiter='\t', quotechar='\"')
            f.readline()  # read the header row; skip
            for line in filereader:
                (stock_genotype_id, stock_id, genotype_id) = line

                stock_key = stock_id
                stock_id = self.idhash['stock'][stock_key]
                genotype_key = genotype_id
                genotype_id = self.idhash['genotype'][genotype_key]

                if self.test_mode \
                        and int(genotype_key) not in self.test_keys['genotype']:
                    continue

                graph.addTriple(stock_id, self.globaltt['has_genotype'], genotype_id)

                line_counter += 1

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

        return