def display_help(self, parser=None):
        if not parser:
            parser = self.parser

        for opt_str in parser.options_to_hide_from_help:
            try:
                parser.remove_option(opt_str)
            except ValueError:
                environment.error(opt_str % "Option %s added for hiding, but it's not in parser...?")

        name = self.name
        print_("\n%s" % name)
        print_("-" * len(name))
        parser.print_help()
        print_()
        print_(self.__doc__)
        print_()
dataset/ETHPy150Open paver/paver/paver/tasks.py/Task.display_help/swapped operands of `%`