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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 make_transcript_gene_se(fn):
 """ Make a Pandas Series with transcript ID's as the index and values as the gene ID containing that transcript. Parameters fn : str Filename of the Gencode gtf file. Returns ------- se : pandas.Series Make a Pandas Series with transcript ID's as the index and values as the gene ID containing that transcript. """

    import itertools as it

    import HTSeq

    gtf = it.islice(HTSeq.GFF_Reader(fn), None)
    transcripts = []
    genes = []
    line = gtf.next()
    while line != '':
        if line.type == 'transcript':
            transcripts.append(line.attr['transcript_id'])
            genes.append(line.attr['gene_id'])
        try:
            line = gtf.next()
        except StopIteration:
            line = ''
   
    return pd.Series(genes, index=transcripts)