<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:

def pmxbot_excuse(self, rest):
        "Provide a convenient excuse"
        args = rest.split(' ')[:2]
        parser = argparse.ArgumentParser()
        parser.add_argument('word', nargs="?")
        parser.add_argument('index', type=int, nargs="?")
        args = parser.parse_args(args)
        if not args.word:
            return self.get()
        return self.find(args.word, args.index)