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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 main(sniffer_instance=None, test_args=(), progname=sys.argv[0], args=sys.argv[1:]):
 """ Runs the program. This is used when you want to run this program standalone. ``sniffer_instance`` A class (usually subclassed of Sniffer) that hooks into the scanner and handles running the test framework. Defaults to Sniffer instance. ``test_args`` This function normally extracts args from ``--test-arg ARG`` command. A preset argument list can be passed. Defaults to an empty tuple. ``program`` Program name. Defaults to sys.argv[0]. ``args`` Command line arguments. Defaults to sys.argv[1:] """

    parser = OptionParser(version="%prog " + __version__)
    parser.add_option('-w', '--wait', dest="wait_time", metavar="TIME",
                      default=0.5, type="float",
                      help="Wait time, in seconds, before possibly rerunning"
                      "tests. (default: %default)")
    parser.add_option('--no-clear', dest="clear_on_run", default=True,
                      action="store_false",
                      help="Disable the clearing of screen")
    parser.add_option('--debug', dest="debug", default=False,
                      action="store_true",
                      help="Enabled debugging output. (default: %default)")
    parser.add_option('-x', '--test-arg', dest="test_args", default=[],
                      action="append",
                      help="Arguments to pass to nose (use multiple times to "
                      "pass multiple arguments.)")
    (options, args) = parser.parse_args(args)
    test_args = test_args + tuple(options.test_args)

    if options.debug:
        print("Options:", options)
        print("Test Args:", test_args)
    try:
        print("Starting watch...")
        run(sniffer_instance, options.wait_time, options.clear_on_run,
            test_args, options.debug)
    except KeyboardInterrupt:
        print("Good bye.")
    except Exception:
        import traceback
        traceback.print_exc()
        return sys.exit(1)
    return sys.exit(0)