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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 _add_gene_list(self, parent_tag, gene_id_dict):
 """Create list of all gene products as sbml readable elements."""

        list_all_genes = ET.SubElement(parent_tag, _tag(
            'listOfGeneProducts', FBC_V2))
        for id, label in sorted(iteritems(gene_id_dict)):
            gene_tag = ET.SubElement(
                list_all_genes, _tag('geneProduct', FBC_V2))
            gene_tag.set(_tag('id', FBC_V2), id)
            gene_tag.set(_tag('label', FBC_V2), label)