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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 write_taxtable(self, out_fp, **kwargs):
 """ Write a taxtable for this node and all descendants, including the lineage leading to this node. """

        ranks_represented = frozenset(i.rank for i in self) | \
            frozenset(i.rank for i in self.lineage())
        ranks = [i for i in self.ranks if i in ranks_represented]
        assert len(ranks_represented) == len(ranks)

        def node_record(node):
            parent_id = node.parent.tax_id if node.parent else node.tax_id
            d = {'tax_id': node.tax_id,
                 'tax_name': node.name,
                 'parent_id': parent_id,
                 'rank': node.rank}
            L = {i.rank: i.tax_id for i in node.lineage()}
            d.update(L)
            return d

        header = ['tax_id', 'parent_id', 'rank', 'tax_name'] + ranks
        w = csv.DictWriter(out_fp, header, quoting=csv.QUOTE_NONNUMERIC,
                           lineterminator='\n')
        w.writeheader()
        # All nodes leading to this one
        for i in self.lineage()[:-1]:
            w.writerow(node_record(i))
        w.writerows(node_record(i) for i in self)