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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 respth2ck(argv=None):
 """Command-line entry point for converting a ReSpecTh XML file to a ChemKED YAML file. """

    parser = ArgumentParser(
        description='Convert a ReSpecTh XML file to a ChemKED YAML file.'
        )
    parser.add_argument('-i', '--input',
                        type=str,
                        required=True,
                        help='Input filename (e.g., "file1.yaml")'
                        )
    parser.add_argument('-o', '--output',
                        type=str,
                        required=False,
                        default='',
                        help='Output filename (e.g., "file1.xml")'
                        )
    parser.add_argument('-fa', '--file-author',
                        dest='file_author',
                        type=str,
                        required=False,
                        default='',
                        help='File author name to override original'
                        )
    parser.add_argument('-fo', '--file-author-orcid',
                        dest='file_author_orcid',
                        type=str,
                        required=False,
                        default='',
                        help='File author ORCID'
                        )

    args = parser.parse_args(argv)

    filename_ck = args.output
    filename_xml = args.input

    properties = ReSpecTh_to_ChemKED(filename_xml, args.file_author, args.file_author_orcid,
                                     validate=True)

    # set output filename and path
    if not filename_ck:
        filename_ck = os.path.join(os.path.dirname(filename_xml),
                                   os.path.splitext(os.path.basename(filename_xml))[0] + '.yaml'
                                   )

    with open(filename_ck, 'w') as outfile:
        yaml.dump(properties, outfile, default_flow_style=False)
    print('Converted to ' + filename_ck)