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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_gffutils_db(gtf, db):
 """ Make database for gffutils. Parameters gtf : str Path to Gencode gtf file. db : str Path to save database to. Returns ------- out_db : gffutils.FeatureDB gffutils feature database. """

    import gffutils
    out_db = gffutils.create_db(gtf,
                                db,
                                keep_order=True,
                                infer_gene_extent=False)
    return out_db