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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 fhirtordf(argv: List[str], default_exit: bool = True) -> bool: """ Entry point for command line utility """

    dlp = dirlistproc.DirectoryListProcessor(argv,
                                             description="Convert FHIR JSON into RDF",
                                             infile_suffix=".json",
                                             outfile_suffix=".ttl",
                                             addargs=addargs,
                                             noexit=not default_exit)

    if not dlp.successful_parse:
        return False

    # Version
    if dlp.opts.version:
        print("FHIR to RDF Conversion Tool -- Version {}".format(__version__))

    # We either have to have an input file or an input directory
    if not dlp.opts.infile and not dlp.opts.indir:
        if not dlp.opts.version:
            dlp.parser.error("Either an input file or an input directory must be supplied")
        return dlp.opts.version

    # Create the output directory if needed
    if dlp.opts.outdir and not os.path.exists(dlp.opts.outdir):
        os.makedirs(dlp.opts.outdir)

    # If we are going to a single output file or stdout, gather all the input
    dlp.opts.graph = Graph() if (not dlp.opts.outfile and not dlp.opts.outdir) or\
                                (dlp.opts.outfile and len(dlp.opts.outfile) == 1) else None
    dlp.opts.fhir_metavoc = load_fhir_ontology(dlp.opts)

    # If it looks like we're processing a URL as an input file, skip the suffix check
    if dlp.opts.infile and len(dlp.opts.infile) == 1 and not dlp.opts.indir and "://" in dlp.opts.infile[0]:
        dlp.infile_suffix = ""
    dlp.outfile_suffix = '.' + suffix_for(dlp.opts.format)
    nfiles, nsuccess = dlp.run(proc=proc_file, file_filter_2=file_filter)
    if nfiles:
        if dlp.opts.graph:
            serialize_graph(dlp.opts.graph, dlp.opts.outfile[0] if dlp.opts.outfile else None, dlp.opts)
        return nsuccess > 0
    return False