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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 get_command_line_arguments():
 """ Retrieves command line arguments. :return: Namespace. :rtype: Namespace """


    parser = argparse.ArgumentParser(add_help=False)

    parser.add_argument("-h",
                        "--help",
                        action="help",
                        help="'Displays this help message and exit.'")

    parser.add_argument("-t",
                        "--title",
                        type=unicode,
                        dest="title",
                        help="'Package title.'")

    parser.add_argument("-i",
                        "--input",
                        type=unicode,
                        dest="input",
                        help="'Input file to convert.'")

    parser.add_argument("-o",
                        "--output",
                        type=unicode,
                        dest="output",
                        help="'Output file.'")

    parser.add_argument("-c",
                        "--content_directory",
                        type=unicode,
                        dest="content_directory",
                        help="'Content directory.'")

    if len(sys.argv) == 1:
        parser.print_help()
        sys.exit(1)

    return parser.parse_args()