How to UT OptionParser()?

How can I unittest this code snippet?

def parse_arguments():
    parser = OptionParser()
    parser.add_option("--debug",
                  action="store_true",
                  default=False)
    parser.add_option("--auto",
                  action="store_true",
                  default=False)

    (params, args) = parser.parse_args()

    return params

I tried to find some example with google but I did not find anything. Thanks