def on_cleanup_error(function, path, excinfo):
                click.secho("warning: failed to remove file or directory: {}\n"
                            "please delete it manually.".format(path),
                            fg="red")
def add_arguments(self, parser):
        parser.add_argument('--noinput', action='store_false',
                            dest='interactive', default=True,
                            help='Do not prompt for input of any kind.')
        parser.add_argument('-l', '--list', action='store_true',
                            dest='list', default=False,
                            help="Just list the requirements, don't install them.")