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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 unified_anib(infiles, org_lengths):
 """Calculate ANIb for files in input directory. - infiles - paths to each input file - org_lengths - dictionary of input sequence lengths, keyed by sequence Calculates ANI by the ANIb method, as described in Goris et al. (2007) Int J Syst Evol Micr 57: 81-91. doi:10.1099/ijs.0.64483-0. There are some minor differences depending on whether BLAST+ or legacy BLAST (BLASTALL) methods are used. All FASTA format files (selected by suffix) in the input directory are used to construct BLAST databases, placed in the output directory. Each file's contents are also split into sequence fragments of length options.fragsize, and the multiple FASTA file that results written to the output directory. These are BLASTNed, pairwise, against the databases. The BLAST output is interrogated for all fragment matches that cover at least 70% of the query sequence, with at least 30% nucleotide identity over the full length of the query sequence. This is an odd choice and doesn't correspond to the twilight zone limit as implied by Goris et al. We persist with their definition, however. Only these qualifying matches contribute to the total aligned length, and total aligned sequence identity used to calculate ANI. The results are processed to give matrices of aligned sequence length (aln_lengths.tab), similarity error counts (sim_errors.tab), ANIs (perc_ids.tab), and minimum aligned percentage (perc_aln.tab) of each genome, for each pairwise comparison. These are written to the output directory in plain text tab-separated format. """

    logger.info("Running %s", args.method)
    blastdir = os.path.join(args.outdirname, ALIGNDIR[args.method])
    logger.info("Writing BLAST output to %s", blastdir)
    # Build BLAST databases and run pairwise BLASTN
    if not args.skip_blastn:
        # Make sequence fragments
        logger.info("Fragmenting input files, and writing to %s", args.outdirname)
        # Fraglengths does not get reused with BLASTN
        fragfiles, fraglengths = anib.fragment_fasta_files(
            infiles, blastdir, args.fragsize
        )
        # Export fragment lengths as JSON, in case we re-run with --skip_blastn
        with open(os.path.join(blastdir, "fraglengths.json"), "w") as outfile:
            json.dump(fraglengths, outfile)

        # Which executables are we using?
        # if args.method == "ANIblastall":
        #    format_exe = args.formatdb_exe
        #    blast_exe = args.blastall_exe
        # else:
        #    format_exe = args.makeblastdb_exe
        #    blast_exe = args.blastn_exe

        # Run BLAST database-building and executables from a jobgraph
        logger.info("Creating job dependency graph")
        jobgraph = anib.make_job_graph(
            infiles, fragfiles, anib.make_blastcmd_builder(args.method, blastdir)
        )
        # jobgraph = anib.make_job_graph(infiles, fragfiles, blastdir,
        #                               format_exe, blast_exe, args.method,
        #                               jobprefix=args.jobprefix)
        if args.scheduler == "multiprocessing":
            logger.info("Running jobs with multiprocessing")
            logger.info("Running job dependency graph")
            if args.workers is None:
                logger.info("(using maximum number of available " + "worker threads)")
            else:
                logger.info("(using %d worker threads, if available)", args.workers)
            cumval = run_mp.run_dependency_graph(
                jobgraph, workers=args.workers, logger=logger
            )
            if 0 < cumval:
                logger.warning(
                    "At least one BLAST run failed. " + "%s may fail.", args.method
                )
            else:
                logger.info("All multiprocessing jobs complete.")
        else:
            run_sge.run_dependency_graph(jobgraph, logger=logger)
            logger.info("Running jobs with SGE")
    else:
        # Import fragment lengths from JSON
        if args.method == "ANIblastall":
            with open(os.path.join(blastdir, "fraglengths.json"), "rU") as infile:
                fraglengths = json.load(infile)
        else:
            fraglengths = None
        logger.warning("Skipping BLASTN runs (as instructed)!")

    # Process pairwise BLASTN output
    logger.info("Processing pairwise %s BLAST output.", args.method)
    try:
        data = anib.process_blast(
            blastdir, org_lengths, fraglengths=fraglengths, mode=args.method
        )
    except ZeroDivisionError:
        logger.error("One or more BLAST output files has a problem.")
        if not args.skip_blastn:
            if 0 < cumval:
                logger.error(
                    "This is possibly due to BLASTN run failure, "
                    + "please investigate"
                )
            else:
                logger.error(
                    "This is possibly due to a BLASTN comparison "
                    + "being too distant for use."
                )
        logger.error(last_exception())
    if not args.nocompress:
        logger.info("Compressing/deleting %s", blastdir)
        compress_delete_outdir(blastdir)

    # Return processed BLAST data
    return data